Публикации

Gavrilova N. N., Sapunov V. N., Skudin V. V. Intensification of dry reforming of methane on membrane catalyst // Chemical Engineering Journal. — 2019. — Vol. 374. — P. 983–991. A kinetic study of dry reforming of methane (DRM) on the traditional powder and membrane catalysts with the active component WC was performed. The paper presents the mass balance of DRM. A kinetic model in which the formation of carbon deposits is absent on both catalysts has been proposed. The model was established that DRM proceeds identically on the traditional and membrane catalysts, that made it possible to propose a kinetic model applicable to both catalysts over the entire range of temperatures, concentrations and flow rates. The rate constant of direct reaction of dry reforming of methane on a membrane catalyst at a temperature of 900 oC is 30 times higher than on a traditional catalyst at the same temperature. This is one more proof of the intensification of catalytic processes with using the membrane catalysts. It has been suggested that the intensification on the membrane catalyst is associated with the features of mass transfer under the conditions of Knudsen diffusion. [ DOI ]

Kinetics on biodiesel oxidation by air oxygen catalyzed by molybdenum complex / Y. Sergey, I. Elena, C. Anna et al. // Petroleum and Coal. — 2019. — Vol. 61, no. 5. — P. 965–972. The proposed method of processing fuels derived from bio-raw materials allows for obtaining products of organic synthesis. The simplified scheme of reactions occurring in the system of oxidizing biodiesel and mathematic description were developed, and they are suitable for non-catalytic as well as Mo-catalyzed oxidation of biodiesel by air oxygen. Kinetic regularities of the process of biodiesel aerobic oxidation were studied by using this kinetic model. It has been found out that Mo-catalyst accelerates formation of all final products including epoxides by means of interaction with peroxyl radicals, i.e. the traditional Sharpless epoxidation mechanism doesn’t match to this case. General parameters of the process, such as air supply speed and temperature do not impact on the character of components concentration curves. Influence of the composition of FAME on the epoxidation selectivity was revealed. The growth of epoxide formation selectivity (up to 85% at 50% – conversion of C-C – double bonds) is observed when mono-/poly-unsaturated compounds ratio is increasing. Thus, fatty acid methyl esters with different unsaturation degree demonstrate tendency to interact in various types of reactions.

Kinetic simulation of initiated cracking of tar /  Gartman, N. T,  Sovetin et al. // Theoretical Foundations of Chemical Engineering. — 2018. — Vol. 51, no. 1. — P. 57–63. A kinetic model of the isothermal initiated cracking of tar has been developed, and parameters of the reactions have been found. A computer model of isothermal thermo-oxidative cracking of tar is implemented to determine kinetic constants, and a criterion for mismatching the calculated and experimental data is minimized. The kinetic simulation of the process has been carried out in isothermal regime so that the parameters that allow for increase in yield of target products have been determined. [ DOI ]

SAPUNOV V., KURGANOVA E., KOSHEL G. Kinetics and mechanism of cumene oxidation initiated by n-hydroxyphthalimide // International Journal of Chemical Kinetics. — 2018. — Vol. 50, no. 1. — P. 3–14. ABSTRACT: This paper discusses the results of investigations on the kinetics of cumene oxidation to cumene hydroperoxide by molecular oxygen in the presence of N-hydroxyphthalimide as a catalyst. A mathematical model has been developed on the basis of the regularities of hydroperoxide and by-products formation. The model adequately describes changes in all reaction components in the course of the reaction. It has also been established that the role of N-hydroxyphthalimide in the process consists in the creation of a steady-state concentration of N-phthalimide radicals initiating oxidation by interacting with the hydrocarbon. C  2017 Wiley Periodicals, Inc. Int J Chem Kinet 50: 3–14, 2018. [ DOI ]

КИНЕТИКА ОКИСЛЕНИЯ МЕТИЛОВЫХ ЭФИРОВ ЖИРНЫХ КИСЛОТ КИСЛОРОДОМ ВОЗДУХА / А. Д. Черепанова, С. А. Юдаев, В. Н. Сапунов, Р. А. Козловский // Химическая промышленность сегодня. — 2018. — № 2. — С. 8–14. Разработаны упрощенная схема и математическая модель реакций, протекающих при окис- лении метиловых эфиров жирных кислот (МЭЖК) кислородом воздуха. Основными продук- тами окисления являются гидропероксиды и эпоксиды соответствующих МЭЖК. Добавление в реакционную среду типичного катализатора гидропероксидного эпоксидирования олефи- нов - комплекса молибденила – лишь незначительно увеличивает селективность образова- ния эпоксидных производных. Предложенная схема и математическая модель подходят для описания процесса, протекающего как без комплекса молибденила, так и в его присутствии. Молибденсодержащий комплекс ускоряет все реакции с участием гидропероксидов или пе- роксильных радикалов. Параметры процесса, такие как расход воздуха и температура, не влияют на характер кинетических кривых. Выявлено сильное влияние состава исходной сме- си метиловых эфиров жирных кислот на селективность эпоксидирования. Рост селективно- сти образования эпоксид-содержащих соединений вплоть до 85% (при конверсии двойных углерод-углеродных связей 50%) наблюдается при увеличении соотношения моно-/полине- насыщенных соединений в исходном сырье, поскольку МЭЖК с разной степенью ненасы- щенности имеют различную реакционную способность в процессе аэробного окисления.

КИНЕТИЧЕСКОЕ МОДЕЛИРОВАНИЕ ПРОЦЕССА ИНИЦИИРОВАННОГО КРЕКИНГА ГУДРОНА / Т. Н. Гартман, Ф. С. Советин, Ю. И. Подсекина и др. // Теоретические основы химической технологии. — 2018. — Т. 52, № 1. — С. 60–67. Разработана кинетическая модель изотермического процесса инициированного крекинга гудрона и определены параметры протекающих реакций. Для определения кинетических констант реализо- вана компьютерная модель изотермического термоокислительного крекинга гудрона и минимизи- рован критерий рассогласования расчетных и экспериментальных данных. Проведено кинетическое моделирование процесса в изотермическом режиме, в результате чего определены параметры, позво- ляющие увеличить выход целевых продуктов. [ DOI ]

Кинетические закономерности процесса олигомеризации бутиллактата при катализе безводным тетрахлоридом олова / И. А. Коноплёв, Т. Н. Гартман, Р. А. Козловский и др. // Химическая промышленность сегодня. – Москва: РХТУ им. Д. И. Менделеева. — 2018. — № 2. — С. 22–30. Исследованы основные кинетические закономерности процесса олигомеризации (поликонденсации) н-бутиллактата при катализе безводным тетрахлоридом олова. Выяснено, что в закрытых условиях (без отвода н-бутанола из зоны реакции)протекают преимущественно реакции образования димера и тримера н-бутиллактата. Показано, что катализатор в процессе поликонденсации находится как в мономерной форме, так и в форме димера тетрахлорида олова, который преимущественно участвует в катализе процесса. Предложена кинетическая модель процесса и найдены основные кинетические параметры (константы скорости и равновесия, энергии активации и предэкспоненциальные множители) с помощью которых адекватно описываются экспериментальные данные.

Cracking of heavy oil residues in a continuous flow reactor, initiated by atmospheric oxygen / V. F. Shvets, V. N. Sapunov, R. A. Kozlovskiy et al. // Chemical Engineering Journal. — 2017. — Vol. 329. — P. 275–282. [ DOI ]

Highly selective process for epoxidation of fatty acid methyl esters with peroxyacetic acid / V. N. Sapunov, M. S. Voronov, S. A. Yudaev et al. // Russian Journal of Applied Chemistry. — 2017. — Vol. 90, no. 10. — P. 1598–1604. Abstract—Specifi c features of the double-stage process in which unsaturated compounds and, in particular, fatty acid methyl esters of vegetable oils are epoxidated with peroxyacetic acid obtained ex situ in aqueous solutions of acetic acid and hydrogen peroxide under catalysis with Amberlyst 15 Dry ion-exchange resin were examined. It was shown that the independently occurring processes in which the peroxy acid is heterogeneously catalytically formed and epoxy compounds are synthesized can substantially raise the formation selectivity of epoxides with respect to double bonds in fatty acid methyl esters and simplify the simulation of these processes and their technological implementation. [ DOI ]

Production of greases from crude glycerol / G. V. DZHABAROV, V. N. SAPUNOV, E. M. MAKAROVA et al. // CHIMICA OGGI-CHEMISTRY TODAY. — 2017. — Vol. 35, no. 3. — P. 48–50. Biodiesel is one of the most promising renewable energy source and its production increases every year. But there is one drawback – need of utilization of glycerol, the main by-product of this process. The article presents methods of utilization of crude glycerol by its thickening with various inorganic salts to produce greases. It was discovered that metal salt reacted with soaps contained in glycerol obtained from biodiesel-production facilities with formation of greases. By-products of these processes was methanol contained in crude glycerol and, in some cases, purified glycerol.

Stearic acid hydrodeoxygenation over pd nanoparticles embedded in mesoporous hypercrosslinked polystyrene / V. N. Sapunov, А. А. Stepacheva, E. M. Sulman et al. // Journal of Industrial and Engineering Chemistry. — 2017. — Vol. 46. — P. 426–435. Stearic acid hydrodeoxygenation into n-heptadecane on the catalyst containing Pd nanoparticles incorporated in the hypercrosslinked polystyrene matrix was studied. The used catalysts were characterized using TEM, CO chemisorption, low-temperature nitrogen physisorption and XPS. A clear hydrogen pressure dependent induction period was noticed. Kinetic regularities were studied for the indicated reaction in the presence of polymer based catalysts. A mathematical model for decarboxylation was suggested which was able to adequately describe experimental data at different temperatures, hydrogen pressures and initial concentrations of stearic acid. Kinetic constants were calculated and their statistical analysis was performed. [ DOI ]

Specific process features of epoxidation of fatty acid methyl esters of vegetable oils with performic acid generated in situ / V. N. Sapunov, M. S. Voronov, S. I. Gustyakova et al. // Russian Journal of Applied Chemistry. — 2017. — Vol. 90, no. 1. — P. 53–62. Physicochemical relationships of the phase distribution of the reactants in epoxidation of fatty acid methyl esters of vegetable oils with performic acid generated in situ were determined.. The progress of epoxidation is accompanied by redistribution of the organic and aqueous phase volumes. The major cause of changes in the phase volumes is the transfer of peroxide oxygen from the aqueous phase into the organic phase upon formation of epoxy groups. A comparable change in the phase volumes is due to reactive extraction of aqueous phase components with the epoxy compounds formed. [ DOI ]

ВЫСОКОСЕЛЕКТИВНЫЙ ПРОЦЕСС ЭПОКСИДИРОВАНИЯ МЕТИЛОВЫХ ЭФИРОВ ЖИРНЫХ КИСЛОТ НАДУКСУСНОЙ КИСЛОТОЙ / В. Н. Сапунов, М. С. Воронов, С. А. Юдаев и др. // Журнал прикладной химии. — 2017. — Т. 90, № 10. — С. 1315–1322. Изучены особенности двустадийного процесса эпоксидирования ненасыщенных соединений, в част- ности метиловых эфиров жирных кислот растительных масел, надуксусной кислотой, получаемой ex situ в водных растворах уксусной кислоты и пероксида водорода при катализе ионообменной смолой Amberlyst 15 Dry. Показано, что протекающие независимо друг от друга процессы гете- рогенно-каталитического образования надкислоты и получения эпоксидных соединений позволяют значительно увеличить селективность образования эпоксидов по отношению к двойным связям в метиловых эфирах жирных кислот, упростить моделирование указанных процессов и их технологи- ческое оформление.

Разработка математической модели процесса эпоксидирования биодизеля в присутствии молибденового катализатора / С. А. Юдаев, Е. Н. Ивашкина, И. О. Долганова и др. // Химическая промышленность сегодня. — 2017. — № 1. — С. 22–33. Приведены экспериментальные данные по окислению метиловых эфиров жирных кислот растительных масел (подсолнечного, рапсового и оливкового масла) кислородом воздуха. Эксперименты проводили в колонном аппарате в присутствии катализатора эпоксидирования – пропилен молибденила. Основ- ными продуктами реакции являлись соответствующие эпоксиды, которые образуются по нескольким путям – при каталитическом эпоксидировании ненасыщенных фрагментов окисляемых эфиров образу- ющимися пероксирадикалами и гидропероксидами. Основной вклад в тепловой эффект процесса вно- сят реакции окислительной деструкции при разрыве двойной связи с образованием альдегидов. Пред- ложена схема процесса окисления и эпоксидирования метиловых эфиров жирных кислот растительных масел и её математическая модель с использованием квантово-химических методов расчета термодина- мических функций для целевых и побочных реакций в совокупности с анализом экспериментальных данных, полученных в результате проведения процесса на различных видах сырья. Выявлены основные закономерности процесса эпоксидирования. Проведена проверка адекватности разработанной модели.

Catalytic hydrodeoxygenation of fatty acids for biodiesel production / À. A. Stepacheva, E. M. Sulman, L. Z. Nikoshvili et al. // BULLETIN OF CHEMICAL REACTION ENGINEERING AND CATALYSIS. — 2016. — Vol. 11, no. 2. — P. 125–132. This paper is devoted to the production of second generation biodiesel via catalytic hydrodeoxygenation of fatty acids. Pd/C catalysts with different metal loading were used. The palladium catalysts were characterized using low-temperature nitrogen physisorption and X-ray photoelectron spectroscopy. It was revealed that the most active and selective catalyst was 1%-Pd/C which allowed reaching up 97.5% of selectivity (regarding to n-heptadecane) at 100% conversion of substrate. Moreover, the chosen catalyst is more preferable according to lower metal content that leads the decrease of the process cost. The analysis of the catalysts showed that 1%-Pd/C had the highest specific surface area compared with 5%-Pd/C. [ DOI ]

Catalytic hydrodeoxygenation of fatty acids for biodiesel production / A. A. Stepacheva, V. N. Sapunov, E. M. Sulman et al. // BULLETIN OF CHEMICAL REACTION ENGINEERING AND CATALYSIS. — 2016. — Vol. 11, no. 2. — P. 125–132. This paper is devoted to the production of second generation biodiesel via catalytic hydrodeoxygenation of fatty acids. Pd/C catalysts with different metal loading were used. The palladium catalysts were characterized using low-temperature nitrogen physisorption and X-ray photoelectron spectroscopy. It was revealed that the most active and selective catalyst was 1%-Pd/C which allowed reaching up 97.5% of selectivity (regarding to n-heptadecane) at 100% conversion of substrate. Moreover, the chosen catalyst is more preferable according to lower metal content that leads the decrease of the process cost. The analysis of the catalysts showed that 1%-Pd/C had the highest specific surface area compared with 5%-Pd/C. Copyright (C) 2016 BCREC GROUP. All rights reserved. [ DOI ]

Fatty acid hydrotreatment using hypercrosslinked polystyrene-supported pd catalysts to produce biofuels: 19th international conference on process integration, modeling and optimization for energy savings and pollution reduction / A. A. Stepacheva, V. G. Matveeva, E. M. Sulman, V. N. Sapunov // Chemical Engineering Transactions. — 2016. — Vol. 52. — P. 625–630. Current work is devoted to the search of novel technologies of biofuel production from non-eatable or waste cooking oils and fats. One of such technique is hydrofining which includes the following processes - hydrodeoxygenation, hydrocracking, hydrogenation - and allows producing 2nd generation biodiesel in form of linear saturated hydrocarbons or alcohols with carbon number of 15-22. Palladium-containing catalytic systems on the base of hypercrosslinked polystyrene (HPS) with different metal loading were studied in stearic acid hydrodeoxygenation and hydrogenation processes to obtain target products (heptadecane and stearyl alcohol) with high yield. It was revealed, that the most effective catalytic system in both processes was the catalyst 1%Pd/MN-270, which allows achieving the high products yield in hydrodeoxygenation process (selectivity regarding n-heptadecane was 99% at 100% substrate conversion) as well as in hydrogenation reaction (selectivity regarding stearyl alcohol was 93% at 100% substrate conversion) of stearic acid. [ DOI ]

Improvement of a process for preparing peracetic acid by the reaction of acetic acid with hydrogen peroxide in aqueous solutions, catalyzed by ion-exchange resins / M. S. Voronov, V. N. Sapunov, A. A. Makarov et al. // Russian Journal of Applied Chemistry. — 2016. — Vol. 89, no. 3. — P. 421–431. The effect of Amberlyst 15Dry (TM) cation-exchange resin on the reaction of peracetic acid formation from acetic acid and hydrogen peroxide in aqueous solution was studied. The pathways of available oxygen consumption were determined. The noncatalytic synthesis is accompanied by spontaneous decomposition of the peracid formed, which sharply decelerates on introducing Amberlyst 15Dry catalyst into the reaction mixture. Comparison of the kinetic relationships of the processes occurring in batch and flow-through reactors shows that in the latter case the process is characterized by diffusion hindrance. A kinetic model of the process with the parameters ensuring adequate mathematical description of the data obtained was suggested. [ DOI ]

New ways to increase the depth of crude oil refining / V. F. Shvets, V. N. Sapunov, R. A. Kozlovskii et al. // Russian Journal of Applied Chemistry. — 2016. — Vol. 89, no. 11. — P. 1806–1815. [ DOI ]

Selective aerobic oxidation of cyclohexyl- and sec-alkylarenes to hydroperoxides in the presence of n-hydroxyphthalimide / E. A. Kurganova, V. N. Sapunov, G. N. Koshel, A. S. Frolov // Russian Chemical Bulletin. — 2016. — Vol. 65, no. 9. — P. 2115–2128. The review summarizes the available scientific and technical information on aerobic oxidation of cyclohexyl- and sec-alkylarenes to tertiary hydroperoxides in the presence of N-hydroxyphthalimide. Kinetics, oxidation mechanism, catalytic and initiating ability of N-hydroxyphthalimide were discussed. [ DOI ]

Аэробное окисление метиловых эфиров жирных кислот растительных масел в присутствии молибденового катализатора / А. Д. Кулажская, С. О. Ларина, М. С. Воронов и др. // Успехи в химии и химической технологии. — 2016. — Т. 30, № 11. — С. 14–16.

ЗАКОНОМЕРНОСТИ ОБРАЗОВАНИЯ НАДМУРАВЬИНОЙ КИСЛОТЫ В ВОДНЫХ РАСТВОРАХ ПЕРОКСИДА ВОДОРОДА И МУРАВЬИНОЙ КИСЛОТЫ / М. С. Воронов, В. Н. Сапунов, А. Д. Кулажская и др. // Химическая промышленность сегодня. — 2016. — № 5. — С. 7–15.

НОВЫЕ ВАРИАНТЫ УГЛУБЛЕНИЯ ПЕРЕРАБОТКИ НЕФТИ / В. Ф. Швец, В. Н. Сапунов, Р. А. Козловский и др. // Журнал прикладной химии. — 2016. — Т. 89, № 11. — С. 1438–1449. Приведены экспериментальные данные по термоокислительному крекингу гудрона и мазута. Экспе- рименты проводились на пилотной установке с реактором непрерывного действия объемом 1.5 л при температурах 430–460oС, давлениях 2–6 атм и с подачей воздуха в реактор в количестве 30–80 л·кг–1. Показано, что в этих условиях по сравнению с термическим крекингом существенно возрастает выход светлых фракций (до 36% для гудрона и до 57% для мазута) с сохранением возможности использова- ния остатков крекинга в качестве котельного топлива или битума. На основании анализа значений выхода углеводородных фракций, полученных при различных параметрах процесса, предложена общая схема превращений исходного сырья в процессе термоокислительных превращений и построена ма- тематическая модель, описывающая все полученные экспериментальные данные.

СОВЕРШЕНСТВОВАНИЕ ТЕХНОЛОГИИ ПОЛУЧЕНИЯ НАДУКСУСНОЙ КИСЛОТЫ ПРИ КАТАЛИЗЕ ИОНООБМЕННЫМИ СМОЛАМИ В ВОДНЫХ РАСТВОРАХ УКСУСНОЙ КИСЛОТЫ И ПЕРОКСИДА ВОДОРОДА / М. С. Воронов, В. Н. Сапунов, А. А. Макаров и др. // Журнал прикладной химии. — 2016. — Т. 89, № 3. — С. 370–380. Исследовано влияние катионообменной смолы Amberlyst 15Dryтм на протекание реакции получения надуксусной кислоты в водных растворах уксусной кислоты и пероксида водорода. Определены пути расходования активного кислорода. При некаталитическом синтезе происходит спонтанное разложе- ние образующейся надкислоты, которое резко замедляется при внесении в реакционную среду ката- лизатора Amberlyst 15Dry. Сопоставление кинетических закономерностей процессов, протекающих в периодическом и проточном реакторах, показало, что в последнем случае проявляется диффузионное торможение. Предложена кинетическая модель процесса, параметры которой обеспечивают адек- ватное математическое описание полученных экспериментальных данных.

Селективное аэробное окисление циклогексил и вторалкиларенов до гидропероксидов в присутствии nгидроксифталимида / Е. А. Курганова, В. Н. Сапунов, Г. Н. Кошель, А. С. Фролов // Известия Академии наук. Серия химическая. — 2016. — № 9. — С. 2115–2128. В обзоре обощены данные по высокоселективному методу аэробного окисления циклогексил" и втор"алкиларенов до третичных гидропероксидов в присутствии N"гидр" оксифталимида. Приведены данные по кинетике процесса, механизму окисления и рас" смотрена каталитическая и инициирующая роль N"гидроксифталимида.

Aromatization of propane–butane fraction over the zncrhzsm-5 catalyst: Kinetic modeling of the process / V. F. Shvets, V. N. Sapunov, R. A. Kozlovskii et al. // Petroleum Chemistry. — 2015. — Vol. 55, no. 8. — P. 632–639. The aromatization reaction of a propanerich propane–butane mixture on an HZSM5 catalyst modified with chromium and zinc ions has been studied in a flow reactor at temperatures in the range of 530–640oC. Kinetic modeling of the process as a heterogeneous catalytic reaction was performed using the experimental data obtained under conditions of unfeasibility of simultaneous maintenance of temperature and space time in each kinetic experiment. The approach proposed has made it possible to reveal the scheme of conversion of the propane–butane reactants to aromatic hydrocarbons, develop a kinetic model of the process, and find its parameters to ensure an adequate mathematical description of the experimental data. [ DOI ]

Preparation of dimethyl-substituted cumene hydroperoxides / A. S. FROLOV, E. A. KURGANOVA, G. N. KOSHEl, V. N. SAPUNOV // CHIMICA OGGI-CHEMISTRY TODAY. — 2015. — Vol. 33, no. 6. — P. 49–56. The article investigates the kinetics of the oxidation reaction of dimethyl cumene to hydroperoxides with molecular oxygen in the presence of N-hydroxyphthalimide.. In order to obtain information on the kinetic laws related to the process of dimethyl cumene oxidation in the presence of N-hydroxyphthalimide, a series of experiments was conducted. The experimental data related to the kinetics of hydroperoxides and non-reaction products formation provided the mathematical model that adequately describes the change of all components of the reaction at the time. It was established that the role of N-hydroxyphthalimide as the initiator of the process is determined by the fact that its interaction with oxygen results in the stationary concentration of N-phthalimide radicals, which initiate oxidation process in their interaction with hydrocarbon. The experimentally tested high-selective method used for the synthesis of hydroperoxides by liquid-phase catalytic dimethyl cumene oxidation can become the basis of a single universal method for producing xylenols that meets the latest environmental and economic requirements. The suggested mathematical model of the dimethyl cumene oxidation to hydroperoxides in the presence of NHPI is original and may be of interest for calculating the kinetics of similar reactions involving other alkylaromatic hydrocarbons.

Studying major kinetic relationships of xylan hydrolysis by a free and immobilized trichoderma viride enzyme complex / V. Sapunov, E. Ozhimkova, V. Doluda, E. Sulman // Journal of biochemical technology. — 2015. — Vol. 6, no. 3. — P. 970–976.

Studying major kinetic relationships of xylan hydrolysis by a free and immobilized trichoderma viride enzyme complex / V. Sapunov, E. Ozhimkova, V. Doluda, E. Sulman // Journal of biochemical technology. — 2015. — Vol. 6, no. 3. — P. 970–976. Today oligosaccharides are widely used in food, drug and cosmetics production. Enzymatic hydrolysis of polysaccharides is one of the prospective ways of oligosaccharide production. This work studies kinetic regularities of xylan hydrolysis using free and immobilized xylanase enzyme produced by Trichoderma viride (endo-1,4-D-xylanase, EC 3.2.1.8). The analysis of kinetic regularities and values of rate constants suggests a hypothesis about some peculiarities of the mechanism of xylan hydrolysis with a free and immobilized enzyme complex. The hypothesis on the insignificant effect of the immobilization on the enzyme complex activity was proposed. The synthesized catalytic system is reusable (at least 10 runs) and can be used for plant glycan hydrolysis to produce oligosaccharides of various polymerization degree.

Ароматизация пропан-бутановой фракции на катализаторе zncrhzsm-5: кинетическое моделирование процесса / В. Ф. Швец, В. Н. Сапунов, Р. А. Козловский и др. // Нефтехимия. — 2015. — Т. 55, № 6. — С. 487–494. Исследована реакция ароматизации обогащенной пропаном пропан-бутановой смеси на катализаторе HZSM-5, модифицированном ионами цинка и хрома, в проточном реакторе в интервале температур 530–640oC. Проведено кинетическое моделирование процесса – гетерогенно-каталитичской реакции по экспериментальным данным, полученным в условиях невозможности одновременного фиксирования температуры и времени контакта в каждом кинетическом эксперименте. Предложенный подход позволил установить схему превращения исходных компонентов пропан-бутановой смеси в ароматические углеводороды, разработать кинетическую модель процесса и найти ее параметры, обеспечивающие адекватное математическое описание полученных экспериментальных данных. [ DOI ]

Определение степени эпоксидирования метиловых эфиров жирных кислот растительных масел хроматографическим способом / М. С. Воронов, Е. М. Макарова, С. И. Густякова и др. // Успехи в химии и химической технологии. — 2015. — Т. 29, № 7. — С. 94–96.

Эпоксидирование метиловых эфиров жирных кислот подсолнечного масла кислородом воздуха / А. Д. Кулажская, С. А. Юдаев, М. С. Воронов и др. // Успехи в химии и химической технологии. — 2015. — Т. 29, № 7. — С. 97–99.

Computation of the solid catalyzed gas phase reactions with a simultaneous choice of the scheme of the reactions for different composition of the initial reaction mixture / T. N. Gartman, F. S. Sovetin, E. A. Proskuro et al. // Chemical Engineering Transactions. — 2014. — Vol. 39. — P. 1009–1014. One of the features of the industrial heterogeneous catalytic reactions is an influence of qualitative and quantitative composition of the initial reaction mixture on the reactions proceeded. At the stage of the laboratory experiments it is possible to find the stoichiometry, kinetic equations and reaction constants for different components of the initial flow of the raw materials. It is important also to take into account multivariant composition of the initial flows. For these purposes we developed and realized an algorithm for using the model with a simultaneous choice of model equations depending on the composition of the initial reaction mixture. The algorithm was checked on the basis of an example of the aromatization of light alkanes with the different composition of the initial mixture. [ DOI ]

Computational algorithm for autothermal heterogeneous catalytic processes in a thin catalyst bed / T. N. Gartman, F. S. Sovetin, E. A. Proskuro et al. // Theoretical Foundations of Chemical Engineering. — 2014. — Vol. 48, no. 3. — P. 273–279. A computational algorithm has been developed for steadystate autothermal heterogeneous catalytic processes occurring in a thin catalytic bed and involving consecutive and parallel reactions. The algorithm is based on a pseudohomogeneous approach to description of chemical reactions over a catalyst. This approach is applicable to processes with arbitrary stoichiometric schemes of reactions. The correctness and convergence of the algorithm have been verified by performing calculations for a process involving one exothermic and two parallel endothermic reactions. [ DOI ]

Kinetics of d-glucose hydrogenation over a ru-containing heterogeneous catalyst / V. G. Matveeva, V. N. Sapunov, M. E. Grigor’ev et al. // Kinetics and Catalysis. — 2014. — Vol. 55, no. 6. — P. 695–704. We studied the kinetics of glucose hydrogenation over a catalyst containing Ru nanoparticles in a supercrosslinked polystyrene matrix. Two hydrogenation pathways, whose rates differ by several orders of magnitude (“fast” and “slow” pathways), were found. The first pathway includes the reaction of glucose from its aqueous solution with hydrogen sorbed on the catalyst’s metal, and the second one includes the reaction of sorbed substrate with hydrogen occurring on the catalyst support due to spillover. A mathematical description of the reaction pathways was proposed, and the most probable scheme of the process was suggested. The role of hydrogen spillover in the kinetics of the occurring processes was considered. [ DOI ]

АЛГОРИТМ РАСЧЕТА АВТОТЕРМИЧЕСКИХ РЕЖИМОВ ГЕТЕРОГЕННО-КАТАЛИТИЧЕСКИХ ПРОЦЕССОВ НА ТОНКОМ СЛОЕ КАТАЛИЗАТОРА / Т. Н. Гартман, Ф. С. Советин, Е. А. Проскуро и др. // Теоретические основы химической технологии. — 2014. — Т. 48, № 3. — С. 294–294.

Алгоритм расчета автотермических режимов гетерогенно-каталитических процессов на тонком слое катализатора / Т. Н. Гартман, Ф. С. Советин, Е. А. Проскуро и др. // Теоретические основы химической технологии. — 2014. — Т. 48, № 3. — С. 294–300. Разработан алгоритм расчета стационарных режимов автотермических гетерогенно-каталитических процессов на тонком слое катализатора с последовательно-параллельными реакциями. В его основу положен псевдогомогенный подход к описанию химических превращений на катализаторе, позволяющий рассчитывать процессы с произвольными стехиометрическими схемами реакций. Корректность и сходимость алгоритма проверена на конкретном примере с одной экзотермической и двумя параллельными эндотермическими реакциями. [ DOI ]

Наренков Р. Ю., Кладова Д. Ю., Сапунов В. Н. Катализ модифицированными цеолитами процесса конверсии метанола в углеводороды // Химическая промышленность сегодня. — 2014. — № 3. — С. 11–19. The catalytic conversion of methanol to hydrocarbons was investigated. The model of the process and the parameters of this model which adequately describes the conversion of methanol and intermediates in the hydrocarbons of various molecular weights has been developed.

Наренков Р. Ю., Кладова Д. Ю., Сапунов В. Н. Превращения линейных углеводородов на цеолитном катализаторе, // Химическая промышленность сегодня. — 2014. — № 8. — С. 18–24. The process of catalytic cracking of some paraffin’s and olefins produced in the processing of methanol,such as MTO (methanol%to%olefin) and MTG (methanol%to%gasoline) was investigated. High%silica zeolite in the H form + 0,5% P2O5 based on ZSM%5 (Si / Al = 220) was used as a catalyst. The catalyst showed high activity in the conversion of linear hydrocarbons in the gaseous and liquid products. In the gaseous reaction products mostly lower olefins dominated. In the liquid products cyclic and aromatic hydrocarbons and compounds which are formed from olefins were determined, but the olefins were not detected. The amount of olefins and aromatic hydrocarbons liquid products increases with contact.

Цимольный метод получения крезолов и ацетона / Г. Н. Кошель, Е. А. Курганова, Ю. Б. Румянцева и др. // Химическая промышленность сегодня. — 2014. — № 1. — С. 11–17. It is found that in the presence of N%hydroxyphthalimid oxidation of para%cymene and a mix meta % and para%isopropyltoluene proceeds with selectivity of formation of their hydroperoxides more than 95 %. With use of a method of extraction of water solutions of methanol hydroperoxide of isopropyltoluene was emitted from products of oxidation and will subject to acid decomposition with formation of cresols and acetone of 98 % at full conversion of isopropyltoluene hydroperoxides.

Sapunov V. N., Enrique R. A. A new interpretation of the bending of alkaline earth metal compounds of monovalent ligands // Humonidodes Technologia y Cienciaa. — 2013. — Vol. 9, no. 6. — P. 1–12. There does exist a relationship with “saturation” of the X···X (X= H, F, CH3, CN, Cl, Br, I) distances in the series Be to Ra compounds. The X···X distances remain practically constant after the M-X distance has increased beyond a certain extent: for each kind of ligand pair, X2, these limiting distances are found to be 4.030.08, 4.050.08, 4.70.1, 4.90.1, 5.150.1, 5.60.1, and 6.20.1 Å respectively. The acceptance of this rule of limiting distances allows for some semi-empirical tests to estimate the linear/bent structures of triatomic molecules. The switch of Dh  C2v symmetry of MX2 is explained by involving the bonded Rydberg-like orbital of two negatively charged X moieties (X = hydride, halide, cyanide and methyl ligands).

D-glucose hydrogenation over ru nanoparticles embedded in mesoporous hypercrosslinked polystyrene / V. Sapunoy, M. Grigoryey, E. Sulman et al. // The journal of physical chemistry. A, Molecules, spectroscopy, kinetics, environment & general theory. — 2013. — Vol. 117, no. 20. — P. 4073–4083. The kinetics of a-glucose hydrogenation on the catalyst containing Ru nanoparticles in the matrix of hypercrosslinked polystyrene was studied. Two routes of the hydrogenation reaction were revealed; their rates differ by several digits. The first route includes the interaction of a-glucose with the spilled-over hydrogen supplied by the catalyst; the second one includes classical interaction of the sorbed substrate with incident hydrogen from the reaction medium. A mathematical description of D-glucose conversion and the change of the catalyst activity by the first method of D-glucose hydrogenation were obtained. The most probable scheme of the process flow was suggested. The main kinetic parameters were calculated. The role of hydrogen spillover phenomenon in the kinetics of the processes is discussed. [ DOI ]

Sapunov V. N., Petukhov, Liubov Petukhova A. A. A. Kinetics of 2-methylbutene-2 epoxidation with 2-methylbutane hydroperoxide // Journal of chemistry and chemical engineering. — 2013. — Vol. 7. — P. 356–363. The kinetics of epoxidation of methylbutene with structurally identical methylbutane hydroperoxide was studied in the presence of a molybdenum catalyst. The analysis of the rate curves suggested the most probable scheme of the process. The revealed features of the process and its mathematical description make it possible to more competently design a reactor unit for the commercial production of isoprene according to the developed scheme. The main kinetic constants were calculated.

The role of n-hydroxyphthalimide in the reaction mechanism of liquid-phase oxidation of p-cymene / V. N. Sapunov, G. N. Koshel, Y. B. Rumyantsev et al. // Petroleum Chemistry. — 2013. — Vol. 53, no. 3. — P. 171–176. The reaction of the liquidphase oxidation of pcymene to hydroperoxide with a selectivity of up to 95% at a hydrocarbon conversion of 25–30% has been studied at a reaction temperature of 80–120oC in the presence of Nhydroxyphthalimide as the catalyst. The catalytic role of Nhydroxyphthalimide has been substantiated. A kinetic model of the liquidphase oxidation reaction in the presence of the catalyst Nhydroxyphthalimide has been developed and adequately described.

Получение биодизеля в субкритическом метаноле в периодическом реакторе / В. Н. Сапунов, А. В. Кустов, В. Л. Ханикян и др. // Химическая промышленность сегодня. — 2012. — № 10. — С. 7–14.

Получение биодизеля в субкритическом метаноле в трубчатом реакторе / В. Н. Сапунов, А. В. Кустов, В. Ф. Жилин и др. // Химическая промышленность сегодня. — 2012. — № 12. — С. 13–20.

Kinetics and mechanism of the catalytic hydration of propylene oxide / R. Shaikhutdinov, A. Petukhov, V. Sapunov et al. // Kinetics and Catalysis. — 2010. — Vol. 51, no. 1. — P. 50–56. The kinetics of propylene oxide hydration in the presence of bis(ethane1,2diol)molybdate is reported. A mathematical description of PO disappearance and propylene glycol formation is suggested. The most probable scheme for the process is presented. The basic kinetic constants are calculated. [ DOI ]

Kinetics and mechanism of the catalytic hydration of 2-methylbutene-2 oxide / R. Shaikhutdinov, L. Petukhova, V. Sapunov et al. // Petroleum Chemistry. — 2010. — Vol. 50, no. 6. — P. 462–467. The kinetics of the hydration of 2-methylbutene-2 oxide in the presence of bis(ethandiol1,2)molybdate has been studied. The mathematical description of oxide consumption and formation of 2-methylbutanediol has been obtained. The most probable scheme for the the process has been proposed. The main kinetic constants have been calculated. [ DOI ]

Kinetics of 2-methylbutene-2 epoxidation with 2-methylbutane hydroperoxide / L. Petukhova, V. Sapunov, K. Kharlampidi, A. Petukhov // Petroleum Chemistry. — 2010. — Vol. 50, no. 5. — P. 381–387. The kinetics of 2-methylbutene-2 epoxidation with 2-methylbutane hydroperoxide was studied in the presence of a molybdenum catalyst. The mathematical description of the hydroperoxide consumption and 2-methyl-butene-2 oxide formation was derived, and the most probable scheme of the process was suggested. The main kinetic constants were calculated. [ DOI ]

КИНЕТИКА И МЕХАНИЗМ КАТАЛИТИЧЕСКОЙ ГИДРАТАЦИИ ПРОПИЛЕНОКСИДА / Р. З. Шайхутдинов, Л. А. Петухова, Н. В. Сапунов и др. // КИНЕТИКА И КАТАЛИЗ, 2010, том 51, № 1, с. 1–6. — 2010. — Т. 51, № 1. — С. 1–6.

The effect of levitated water on fermentation kinetics / V. Sapunov, R. Schmid, I. Litvintsev, M. Egrebberger // Water Research. — 2004. — Vol. 38, no. 2. — P. 385–392. The rate of anaerobic glucose fermentation by baker's yeast is found to be altered when tap water is replaced with "levitated" (i.e., hydrodynamically processed) water. To analyze the effect in more detail, we developed a fermentation kinetics model that differentiates between (i) nutrient transport into the cell, (ii) the "catabolic" and (iii) the "anabolic" reactions. As a result, the levitated water affects specifically the glucose uptake kinetics, whereas the other kinetic parameters remain unchanged. Remarkably, the sign of the effect changes with the water used to prepare the culture. When levitated water is used for both the culture preparation and the fermentation, the rate constant of glucose transport is increased by (67 +/- 25)%, relative to ordinary tap-water. When the culture is prepared in ordinary water and only the fermentation is performed in levitated water, the rate constant of glucose transport decreased by (50 +/- 12)%. Three-week old levitated water has no discernable effect any more. (C) 2003 Elsevier Ltd. All rights reserved. [ DOI ]

The importance of interligand interactions to structure and reactivity of coordinatively unsaturated ruthenium and iron half-sandwich complexes - application of the tsc concept ii / V. Sapunov, R. Schmid, K. Kirchner, H. Nagashima // Coordination Chemistry Reviews. — 2003. — Vol. 238. — P. 363–382. The interaction between any fragments bonded to some central atom are increasingly recognized as an important factor in determining, e.g. the geometry and properties of metal complexes. Here we analyze the class of the two-legged piano stool complexes Cp'ML2 (Cp' = cyclopentadienyl or a derivative, M = Fe(11) and Ru(11), L = phosphorus and nitrogen co-ligands) with the aid of the through-space coupling (TSC) concept. This is the molecular orbital representation of van der Waals-like repulsive-attractive forces between the ligands in addition to the interactions with the metal center. The combination of both, i.e. the interaction between the new collective ligands orbitals and the metal AO's is shown to be the main determinant for deciding whether a planar or pyramidal structure is adopted and further, whether the complex is diamagnetic or paramagnetic. In addition the TSC concepts aids in understanding the effect of intercomplex interactions on the nucleophilic and electrophilic behavior of the 16e-complexes towards an incoming ligand. In fact, interpretations hitherto solely in terms of electronic ligand effects appear to be inadequate. The present paper is a continuation of our former work in which we successfully applied the TSC concept to rationalize the diverse array of structural arrangements as well as reactivities of the main-group Cp metal complexes (Sapunov et al. Coord. Chem. Reviews 214 (2001) 143). (C) 2001 Elsevier Science B.V. All rights reserved. [ DOI ]

Coordinatively unsaturated ruthenium phosphine half-sandwich complexes: Correlations to structure and reactivity / H. Aneetha, M. Jimenez-Tenorio,  Puerta et al. // Organometallics. — 2002. — Vol. 21, no. 24. — P. 5334–5346. A number of 16e two-legged piano-stool complexes [Cp*Ru(PP)] [BAr'(4)] have been prepared by reaction of NaBAr'(4) with either [CP*RuCl(PP)] (PP = (PEt3)(2), (Pr2PCH2CH2PPr2)-Pr-i-Pr-i (dippe), (PPh3)(2)) or [Cp*RuCl(PR3)] plus PR3 (PR3 = (PMePr2)-Pr-i, (PPhPr2)-Pr-i) in fluorobenzene under argon. The complexes [Cp*Ru(PEt3)(2)] [BAr'(4)], [Cp*Ru(dippe)] [BAr'(4)], and [Cp*Ru(PMeiPr(2))(2)] [BAr'(4)] have been structurally characterized by X-ray crystallography. Attempts to isolate analogous species containing other phosphine ligands such as (PPr3)-Pr-i, PCy3, and PMe3 led to the sandwich derivative [CP*Ru(eta(6)-FPh)] [BAr'(4)], which was also structurally characterized. Both [CP*Ru-(PPh3)(2)] [BAr'(4)] and [Cp*Ru((PPhPr2)-Pr-i)(2)] [BAr'(4)] are unstable and rearrange to the 18e sandwich species [Cp*Ru(eta(6)-C6H5PR2)] [BAr'(4)] and to [Cp*Ru(eta(6)-C6H5POR2)][BAr'(4)] (R = Ph, Pr-i) under trace amounts of oxygen. The geometry of the 16e complexes as well as their affinity for an additional ligand depend on the substituents on the phosphorus. The reactivity with respect to the addition of N-2, PR3, O-2, H-2, and HCl to form 18e derivatives has been studied. Some model systems have been analyzed using density functional theory (DFT) calculations. Also included are comparative studies on the NN counterparts. The moieties [CpRu(PP)](+) (PP = (PH3)(2), H2PCH2CH2PH2) adopt typically pyramidal structures (i.e. in the absence of bulky and rigid substituents on P) versus planar structures of [CpRu(NN)](+) (NN = (NH3)(2), H2NCH2CH2NH2). [CpRu(PP)](+) is more stable but has nevertheless a higher affinity of adding a a ligand than [Cp*Ru(NN)](+). [ DOI ]

Selective c-c bond formation between alkynes mediated by the [rucp(pr3)](+) fragment leading to allyl, butadienyl, and allenyl carbene complexes - an experimental and theoretical study / E. Ruba, K. Mereiter, R. Schmid et al. // Chemistry - A European Journal. — 2002. — Vol. 8, no. 17. — P. 3948–3961. The reaction of alkynes with [RuCp(PR3)(CH3CN)(2)]PF6 (R=Me, Ph, Cy) affords, depending on the structure of the alkyne and the substituent of the phosphine ligand, allyl carbene or butadienyl carbene complexes. These reactions involve the migration of the phosphine ligand or a facile 1,2 hydrogen shift. Both reactions proceed via a metallacyclopentatriene complex. If no alphaC-H bonds are accessible, allyl carbenes are formed, while in the presence of alphaC-H bonds butadienyl carbenes are typically obtained. With diphenylacetylene, on the other hand, a cyclobutadiene complex is formed. A different reaction pathway is encountered with HCequivalent toCSiMe(3), ethynylferrocene (HCequivalent toCFc), and ethynylruthenocene (HCequivalent toCRc). Whereas the reaction of [RuCp(PR3)-(CH3CN)(2)]PF6 (R=Ph and Cy) with HCequivalent toCSiMe(3) affords a vinylidene complex, with HCequivalent toCFc and HCequivalent toCRc this reaction does not stop at the vinylidene stage but subsequent cycloaddition yields allenyl carbene complexes. This latter C-C bond formation is effected by strong electronic coupling of the metallocene moiety with the conjugated allenyl carbene unit, which facilitates transient vinylidene formation with subsequent alkyne insertion into the Ru=C bond. The vinylidene intermediate appears only in the presence of bulky substituents of the phosphine coligand. For the small R=Me, head-to-tail coupling between two alkyne molecules involving phosphine migration is preferred, giving the more usual allyl carbene complexes. X-ray structures of representative complexes are presented. A reasonable mechanism for the formation of both allyl and allenyl carbenes has been established by means of DFT calculations. During the formation of allyl and allenyl carbenes, metallacyclopentatriene and vinylidene complexes, respectively, are crucial intermediates. [ DOI ]

Revisiting the main group cyclopentadienyl metal complexes in terms of the through-space coupling concept / V. Sapunov, K. Kirchner,  Schmid, E. I. MAR FANHA // Coordination Chemistry Reviews. — 2001. — Vol. 214. — P. 143–185. The structures and properties of metal complexes are traditionally treated in terms of hybridization and electronic ligand effects. What is notoriously neglected, however, is the fact that in such an aggregate the ligands approach so closely to one another - on the order of van der Waals (vdW) distances - that intramolecular packing effects come into play. Actually, non-bonded interactions between ally atoms bonded to some central atom are increasingly recognized as an important factor in determining bond distances, bond angles and the like. The class of the main group cyclopentadienyl (Cp) metal complexes appears to be a case study in this respect, because of the large extension of the Cp group and its ring structure on the one hand, and on the other, the minimal d-orbital involvement, dissimilar to the transition-metal analogues. It is shown that the diverse array of structural arrangements, such as linear, ring-slipped, bent, and polymeric chain structures, as well as their reactivities, are brought under the umbrella of one treatment with the aid of the through-space coupling (TSC) concept. This is the molecular orbital representation of vdW repulsive-attractive forces. As a central feature, the individual ligands are at first combined to a united system of TSC orbitals and then allowed to interact with the metal AOs. The energy splitting of the TSC orbitals and the electron density shift from one of them to a vacant metal orbital determine the repulsive and attractive interligand forces and hence fine-tune the geometry of the complex. Along these lines a physical explanation for the interplay between vdW attraction and repulsion becomes available. More specifically we are dealing here with complexes of the type Cp-n'MLm (n = 1-3, m = 0-3) via united {Cp-n'm} molecular orbitals. Bending and slipping of the Cp' ligands are rooted in vdW attraction and repulsion, respectively, with geometry and hapticity of the Cp'-metal bending adjusted so as to optimize TSC. (C) 2001 Elsevier Science B.V. All rights reserved. [ DOI ]

Schmid R., Miah A. M., Sapunov V. N. A new table of the thermodynamic quantities of ionic hydration: values and some applications (enthalpy–entropy compensation and born radii) // Physical Chemistry Chemical Physics. — 2000. — Vol. 2, no. 1. — P. 97–102. Absolute single-ion thermodynamic quantities of hydration at 298.15 K are derivable from the conventional enthalpies and entropies if the values of So(Haq+) and ΔhydHo(H+) are known. Here we suggest So(Haq+) = −5.5 J K−1 mol-1 based on the thermodynamics of the dissociation of water. This assignment, in turn, corresponds to ΔhydHo(H+) = −1078 kJ mol-1 according to a self-consistent analysis of Krestov. Using these values, as a main result, the anions are more strongly hydrated than usually thought, in line with recent calculations. Only the group 1, 2, and 15 nobel gas ions are dealt with. For each series, the conventional enthalpies and entropies are linearly related to one another. From these linear free energy relationships (LFERs) a relationship between So(Haq+) and ΔhydHo(H+) is derived. Further, a connection is detected between the Born radii rB, calculated from the free energies of hydration, and the distances d, corresponding to the upper limits of the experimental first peak position of the ionoxygen radial distribution curves, upon implication, in the case of a cation, the covalent radius rcov of oxygen, and in the case of an anion, the water radius rwater, Finally, from the differences between the enthalpies and free energies of hydration the temperature derivatives of the Born radii are determined. [ DOI ]

Cationic 16-electron half-sandwich ruthenium complexes containing asymmetric diamines: understanding the stability and reactivity of coordinatively unsaturated two-legged piano stool complexes / C. Gemel, V. Sapunov, K. Mereiter et al. // Inorganica Chimica Acta. — 1999. — Vol. 286, no. 1. — P. 114–120. The cationic 16e complexes [RuCp*(eta(2)(N,N)-Me2NCH2CH2N(CH2CHMe2)(2))](+) (1) and [RuCp*(eta(2)(N,N)-Me2NCH2CH2NCH2CH2OCH2CH2](+) (2) as well as the 18e complex [RuCp*(eta(6)-C6H5-N(Me)NCH2CH2NMe2)](+) (3) have been synthesized as the BAr'(4) (Ar' = 3,5-C6H3(CF3)(2)) salts in one-pot reactions starting from [RuCp*(Cl-4)]. For 1, the X-ray crystal structure has also been determined showing the absence of any agostic interactions between ruthenium and the C-H bonds of the diamine ligand, and only minor deviations from the planar geometry despite the bulky diamine ligand. Based on EPI model calculations, the extraordinary kinetic inertness of the planar 16e [Cp*Ru(NN)](+) structure is traced to a high HOMO-LUMO gap deriving from through-bond coupling through the intervening sigma skeleton of the chelating diamine (NN) ligand tin contrast to the P analogs) and further to the high pi donor strength of Cp* (relative to parent Cp). Possible ligand rearrangements to increase the chemical reactivity are analyzed. (C) 1999 Elsevier Science S.A. All rights reserved. [ DOI ]

Activation of η5-cyclopentadienyl ligands toward nucleophilic attack through η5→ η3ring slippage. kinetics, thermodynamics, and nmr spectroscopy / W. Simanko, V. N. Sapunov, R. Schmid et al. // Organometallics. — 1998. — Vol. 17, no. 12. — P. 2391–2393. The kinetics of the reactions of the complexes [Ru(è5-C5H5)(è4-C5H4O)(L)]CF3SO3 (L ) CH3CN, pyridine, thiourea) with PMe3 have been studied in acetone. The novel reaction products [Ru(è3-C5H5)(è4-C5H4O)- (PMe3)(L)]CF3SO3 formed are fluxional in solution due to an intramolecular enantiomeric equilibrium likely proceeding through a five-coordinate è1-C5H5 intermediate. [ DOI ]

Sapunov V., Litvintsev I., Mikhailyuk A. Kinetics and mechanism of catalytic hydroxylation of phenols with hydrogen peroxide: Vi. the physical model and reaction mechanism // Kinetics and Catalysis. — 1998. — Vol. 39, no. 3. — P. 339.

Kinetics and mechanism of nucleophilic substitutions on coordinated polyenes and polyenyls. 3. activation of eta(5)-cyclopentadienyl ligands toward nucleophilic attack through eta(5)->eta(3) ring slippage and a comparison with reaction at c5h4o / W. Simanko, W. Tesch, V. Sapunov et al. // Organometallics. — 1998. — Vol. 17, no. 26. — P. 5674–5688. Complexes of the types [Ru(eta(5)-C5H5)(eta(4)-C5H4O)](2)(CF3SO3)(2) (1) and [Ru(eta(5)-C5H5)(eta(4)-C5H4O)(L)]CF3SO3 (L = CH3CN (2), pyridine (3), thiourea (4)) react with tertiary phosphines to give (i) 1,1'- (12) or (ii) 1,2-disubstituted ruthenocenes (13) depending primarily on the basicity of the entering phosphine and the nature of L. Path i proceeds via the intermediacy of [Ru(eta(3)-C5H5)(eta(4)-C5H4O)(PR3)](2)(2+) (5) and [Ru(eta(3)-C5H5)(eta(4)-C5H4O)(PR3)(L)](+) (6-8); i.e., the hapticity of the C5H5 ligand is changed from eta(5) to eta(3) while forming an additional Ru-P bond. The eta(3) bonding mode was established by H-1 and C-13{H-1} NMR spectroscopies. The kinetics of these reactions were studied in detail, providing enthalpies and entropies of both activation and reaction. The conversions to 6-8 are exothermic (Delta H degrees = -5.5 to -16.9 kcal mol(-1)) but entropically unfavorable (Delta S degrees = -44.8 to -19.0 cal K-1 mol(-1)). The activation parameters and rate constants vary little with the phosphine, suggesting a preequilibrium between eta(5) and eta(3) species of the starting complexes where the latter reacts with the entering phosphine in the rate-determining step. The new eta(3)-C5H5 complexes are, with the exception of 5, fluxional in solution due to an intramolecular enantiomeric equilibrium likely proceeding through a five-coordinate eta(1)-C5H5 intermediate. Path ii proceeds via eta(3)-cyclopentenoyl complexes of the type [Ru(eta(5)-C5H5)(eta(3)-C5H4O-2-PR3)(L)](+) (9-11). Furthermore, 3 and 4 react with small and basic phosphines PR3 = PMe3 and Me2PCH2PMe2 to give the half-sandwich complexes [RU(eta(5)-C5H4OH)(PR3)(2)L](+) (14, 15) together with free C5H4PR3 (16). [ DOI ]

Labile complexes of the [rutp(pn)](+) (tp equals tripyrazolylborate, pn equals ph(2)pch(2)ch(2)nme(2)) fragment including the dinitrogen ligand / G. Trimmel, C. Slugovc, P. Wiede et al. // Inorganic Chemistry. — 1997. — Vol. 36, no. 6. — P. 1076–1083. The [TpRu(pn)](+) fragment (Tp = tripyrazolyl, pn = Ph(2)PCH(2)CH(2)NMe(2)), featuring a strong sigma accepter and a weak pi donor, forms reversible complexes with a variety of sigma donor ligands L including N-2 which appears to be more strongly bonded than even CH3CN. X-ray crystal structures of the complexes with L = H2O, acetone, CO, N-2, and vinylidene are included (adding to that for L = CH3CN from former work), as well as a comparative MO study on the bonding nature of L. The sequence of complex stabilities of [TpRu(pn)L](+) is CF3SO3- < acetone approximate to H2O < CH3CN < N-2 < CO < vinylidene as suggested from EHMO calculations and crystallographic data as well as qualitative experimental results. Despite the notable stability of [TpRu(pn)(eta(1)-N-2)](+), the N-N bond length is 1.097(5) Angstrom, exactly that in free N-2. Our analysis suggests that the insensitivity of the N-N bond essentially originates from the counterbalance of pi bond weakening (through back-donation) and sigma bond strengthening (through reducing the antibonding character of the sigma* (2 sigma(u)) MO in molecular dinitrogen. [ DOI ]

Oxidation of ruthenium(ii) to ruthenium(iv) eta(4)-diene complexes: Swing mechanism and diene-allyl conversion / C. Gemel, D. Kalt, K. Mereiter et al. // Organometallics. — 1997. — Vol. 16, no. 3. — P. 427–433. This paper reports on the synthesis and reactivity of Ru(IV) eta(4)-diene complexes of the type Ru(eta(5)-C(5)Me(5))(eta(4)-diene)Br-2(+) obtained by oxidative bromine additions to Ru(II) eta(4)-diene complexes. Mechanistic details are derived from the reaction products varying with the oxidizing agent and the leaving ligand and are backed up by extended Huckel molecular orbital calculations. The diene fragment in Ru(IV) is prone to gauche deformation and is therefore extremely susceptible to nucleophilic attack of even weak anionic bases generating the corresponding Ru(IV) eta(3)-allyl complexes. Accordingly, Ru(IV) eta(4)-diene complexes are stabilized either by using 2,3-disubstituted diene ligands in which case gauche deformation is highly unfavorable or else by excluding nucleophilic agents. For the latter method, two convenient routes to affording Ru(IV) eta(4)-diene complexes are (i) the reaction of Br+CF3SO3- with Ru(eta(5)-C(5)Me(5))(eta(4)-diene)Br and (ii) the reaction of dibromine with labile Ru(eta(5)-C(5)Me(5))(eta(4)-diene)(CF3SO3). The conversion of the Ru(II) eta(4)-diene to the Ru(IV) eta(4)-diene complex is suggested to proceed via a swing of the diene ligand by changing the dihedral angle between the C(5)Me(5) and diene ligands from about +20 to about -70 degrees concomitantly pushing the leaving ligand (Br- or CF3SO3-) out. [ DOI ]

Ruthenium(ii) tris(pyrazolyl)borate complexes. reversible vinylidene complex formation / C. Slugovc, V. Sapunov, P. Wiede et al. // JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS Выпуск: 22 Стр.: 4209-4216. — 1997. — Vol. 22. — P. 4209–4216. A convenient high-yield route to [Ru{HB(pz)3}Cl(PPh3)(=C-CHR)] (pt = pyrazolyl; R = Ph,SiMe3, Bu-u, Bu-t, CO2Et or C6H9) has been found through the intermediary [Ru{HB(pz)(3)}(PPh3)(dmf)] (dmf = dimethyl- formamide) which has been crystallographically characterized. This complex is readily obtained on treatment of [Ru{HB(pz)(3)}Cl(cod)] (cod = cycloocta-1,5-diene) with 1 equivalent of PPh3 in boiling dmf. The vinylidene moiety in complexes of the type [Ru{HB(pz)(3)}Cl(PPh3)(=C-CHR)] is remarkably labile being easily replaced by nucleophiles L = PMe3, PPh3, MeCN, pyridine or CO to give [Ru{HB(pz)(3)}Cl(PPh3)L]. With the exceptions of L = PMe3 or CO, these reactions are reversible. The complex [Ru{HB(pz)(3)}Cl(PPh3)(CO)] has been characterized by X-ray crystallography. On treatment of [Ru{HB(pz)(3)}Cl(PPh3)(=C-CHPh)] with an excess of HC=CR' (R' = SiMe3, Bu-n, Bu-t, CO2Et or C6H9) the neutral vinylidene complex [Ru{HB(pz)(3)}Cl(PPh3)(=C=CHR')] was reversibly formed. Comparative studies and extended-Huckel molecular orbital calculations have been performed to elucidate the nature of the bonding in the various vinylidene complexes. The bonding between the metal center and the vinylidene ligand is dominated by the d(yz) (metal)-p (vinylidene) interaction If this contribution is small, reconversion of the vinylidene complex into an eta(2)-alkyne complex can be accomplished. [ DOI ]

Structure and bonding in a series of cyano complexes: Rucp(pph3)(2)cn, [rucp(pph3)(2)(cnh)]cf3so3, and h-bridged [ru-2(cp)(2)(pph3)(4)cnhnc]cf3so3 /  Sapunov,  VN, K. Mereiter et al. // Journal of Organometallic Chemistry. — 1997. — Vol. 530, no. 11. — P. 105–115. The three title cyanoruthenium complexes have been characterized by means of X-ray diffraction analysis, IR and NMR solution spectroscopies, as well as extended Huckel molecular orbital calculations examining the properties of the cyanide fragment changing with complexation and with the co-ligands Cp and PPh3. Explanations are given for crystallographic results of the C-N bond shortening upon complexation, the supershort (2.573 Angstrom) bond length of N(H)... N in the bridged complex, as well as the Ru-C-N and C-N-H-N-C bendings. Although the crystallographically found asymmetry of coordinated Cp is not significant, the MO calculations suggest a distorted endocyclic bond-length pattern indicative of the relative importance of sigma and pi bonding in the metalcyclopentadienyl interactions. [ DOI ]

Structure, bonding, and reactivity of molybdenum eta(3)-cyclohexenone complexes in comparison with their cyclopentenone analogues: eta(3)-allyl/eta(4)-diene conversion / V. Sapunov, C. Slugovc, K. Mereiter et al. // JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS. — 1997. — Vol. 19. — P. 3599–3604. The neutral eta(3)-cyclohexenone complexes [Mo(eta(3)-C6H7O)(CO)(2)(MeCN)(2)Br] 1, [Mo(eta(3)-C6H7O)(CO)(2){HB(pz)(3)}] 2, [Mo(eta(3)-C6H7O)(CO)(2)(bipy)Br] 3 (bipy = 2,2'-bipyridine) and [Mo(eta(3)-C6H7O)(CO)(2)(dppm)Br] 4 (dppm = Ph2PCH2PPh2) have been synthesized. The structure of 2 has been determined by X-ray crystallography. All these complexes resist hydride abstraction using Ph3C+PF6-, in sharp contrast to the eta(3)-cyclopentenone analogues where eta(3)-allyl/eta(4)-diene conversion is a facile process. A rationale for this different behaviour is provided by extended-Huckel calculations combined with a Walsh analysis of hydrogen abstraction. Thus, while in the eta(3)-C5H5O –> eta(4)-C5H4O conversion a Mobius system is formed upon release of hydride via electrophilic attack, this is not possible in the hypothetical eta(3)-C6H7O –> eta(4)-C6H6O process. Therefore, eta(3)-C6H7O is a C-H acid. Also, the occurrence of different conformations, exo for allyl and endo for diene complexes, is rationalized. [ DOI ]

Litvintsev I., Timofeev S., Sapunov V. Kinetics and mechanism of catalytic hydroxylation of phenol by hydrogen peroxide .4. modeling of the stage of dihydroxybenzene oxidation // Kinetics and Catalysis. — 1996. — Vol. 37, no. 2. — P. 193–201. The kinetics of individual and combined peroxide oxidation of target products of the catalytic hydroxylation of phenol to dihydroxybenzenes, i.e., pyrocatechol and hydroquinone, in the presence of homogeneous catalysts (iron sulfate and its complex with pyrocatechol:) is studied under conditions typical of this process. The series of one-factor experiments results in the development of mathematical models that adequately describe the principles observed. The possible mechanism of individual and combined oxidation of dihydroxybenzenes is discussed.

Modelling of processes of hydroperoxide epoxidation of olefins. influence of an olefin on the activity of the decomposition catalyst for ethylbenzene hydroperoxide / R. Akhmedyanova, A. Monayenkov, I. Litvintsev, V. Sapunov // Petroleum Chemistry. — 1996. — Vol. 36, no. 1. — P. 78–82. An investigation has been made of the influence of additions of an olefin (Ol) (nonene, cyclohexene) on the kinetics of consumption of ethylbenzene hydroperoxide (EBHP) in the presence of a complex molybdenum-containing catalyst (CMC). It has been shown that, despite the change in the activity of the catalyst in the decomposition reaction under the influence of the epoxidation products, the three routes of EBHP consumption that were found earlier are maintained. The presence of monomeric and oligomeric forms of the catalyst must also be taken into account in the modelling of epoxidation. (C) 1996 Elsevier Science Ltd. All rights reserved.

Modelling of processes of hydroperoxide epoxidation of olefins. reaction of butadiene with tert-amyl hydroperoxide / R. Akhmedyanova, A. Liakumovich, I. Litvintsev et al. // Petroleum Chemistry. — 1996. — Vol. 36, no. 1. — P. 83–92. An investigation has been made of the general relationships governing the epoxidation of butadiene by organic hydroperoxides (TAHP, TBHP, IPBHP, EBHP) with catalysis by molybdenyl propylene glycolate, and a detailed study has been made of the kinetics of the reaction for tert-amyl hydroperoxide. A mathematical model of the process has been developed, adequately describing the experiment with variation in [TAHP](0) from 0.5 to 1.5 mole/l and in [Cat](0) from 3 to 8 x 10(-4) mole/l at a temperature of 110 degrees C, and taking account of the change in activity of the catalyst as a function of [Cat] and [ROOH](0). The complex influence of additions of an alcohol, which inhibits the epoxidation rate, but at the same time increases the proportion of the active form of the catalyst, has been explained. The generality of the effects observed for all the examined reactions of hydroperoxide oxidation has been confirmed, and also the need to allow for change in the state of the catalyst in the solution during modelling of these processes. (C) 1996 Elsevier Science Ltd. All rights reserved.

Ruthenium tris(pyrazolyl)borate complexes. formation and characterization of acetone, dimethylformamide and vinylidene complexes containing n,n-donor co-ligands / C. Gemel, P. Wiede, K. Mereiter et al. // JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS. — 1996. — Vol. 21. — P. 4071–4076. Chloride abstraction from [Ru{HB(pz)(3)}(tmen)Cl] (pz = pyrazolyl, tmen = Me(2)NCH(2)CH(2)NMe(2)) with NaBPh(4) in the solvents acetone and dimethylformamide led to the formation of the respective cationic [Ru{HB(pz)(3)}(tmen)(solv)](+) complexes. In the presence of phenylacetylene, these are easily transformed into the first example of a ruthenium HB(pz)(3) vinylidene complex. Extended-Huckel molecular-orbital calculations have been performed to establish the nature of the bonding involved. From [Ru{HB(pz)(3)}(py)(2)Cl] (py = pyridine) the corresponding vinylidene complex could be prepared in the same way, although the intermediate solvent complexes could not be isolated. Selected crystal structures were determined. [ DOI ]

Development of new technology for the synthesis of 1,2-cyclohexanediol as a stage of pyrocatechol production / M. SEMENOV, A. KOMAROV, A. MIKHAILYUK et al. // Petroleum Chemistry. — 1995. — Vol. 35, no. 2. — P. 111–115. Data are given on the operation of a pilot unit for the production of 1,2-cyclohexanediol, a semiproduct in the process chain proposed for the synthesis of pyrocatechol. On the basis of the work carried out, the optimum conditions for the process of 1,2-cyclohexanediol production have been determined. It has been shown that, for the selective production of 1,2-cyclohexanediol, the heterophase reaction of hydrogen peroxide with cyclohexene must be carried out under the following conditions: temperature 40-70 degrees C; the initial hydrogen peroxide concentration is no higher than 35 mole/l; maximum initial concentration of heteropolyphosphoric acid 0.014 mole/l; initial concentration of interphase transfer catalyst 0.011 mole/l; volume ratio of organic and aqueous phases 2:1. Under these conditions of the heterophase reaction of hydrogen peroxide with cyclohexene, the target product (1,2-cyclohexanediol) yield amounts to at least 80-90 mol.%.

LITVINTSEV I., MIKHAILYUK A., SAPUNOV V. Kinetics and mechanism of catalytic hydroxylation of phenol by hydrogen-peroxide .3 // Kinetics and Catalysis. — 1995. — Vol. 36, no. 4. — P. 482–487. The qualitative and quantitative effects of various metal salt additives to iron sulfate on the parameters of the hydroxylation process are investigated. Synergism is observed only on addition of metal salts that do not possess any catalytic activity of their own. The maximum simbatic effect of increasing both the initial rate and the selectivity of the process is revealed in the case of cocatalysis by iron and cerium sulfates. The kinetics of phenol hydroxylation by hydrogen peroxide in the presence of the previously prepared complex of iron and cerium sulfates with catechol is examined in detail. The method of the initial rates is used to obtain the data for developing a model that adequately describes all regularities observed in the range of the initial concentrations of both the reagents 0.25 - 3.0 mol/l and the catalytic system 1 x 10(-5) - 1 x 10(-3) mol/l (with respect to iron sulfate). A comparative analysis of the models of the initial stage of the reaction catalyzed by the FeSO4-catechol system and its analog modified by Ce(SO4)(2) is performed.

LITVINTSEv I., MIKHAILYUK A., SAPUNOV V. Kinetics and mechanism of catalytic hydroxylation of phenol by hydrogen-peroxide .4. regularities of active catalyst formation // Kinetics and Catalysis. — 1995. — Vol. 36, no. 4. — P. 488–491. The processes occurring at the initial stage of phenol oxidation by peroxide catalyzed by FeSO4 are investigated. The duration of the stage of selective benzoquinone formation is found to be primarily a function of the pH of the medium. In the presence of the monohydrate of tervalent iron and catechol (CT) in the reaction solution, a [Fe2+(OH).CT] complex that is active in hydroxylation is rapidly formed, which results in a complete change of the reaction pathway. The main regularities of this complex formation are established. A hypothesis on the nature of the catalyst species responsible for each pathway is put forward. Taking into account the UV and ESR spectroscopic data and the results of photochemical phenol oxidation by hydrogen peroxide, the likely mechanism of the initial stage of phenol oxidation by peroxide is discussed. The effect of cerium sulfate additives on the duration of the induction period and on the hydroxylation rate is explained.

Catalytic decomposition of ethylbenzene hydroperoxide - complete model of the process / R. AKHMEDYANOVA, I. LITVINTSEV, A. MONAYENKOV, V. SAPUNOV // Petroleum Chemistry. — 1994. — Vol. 34, no. 6. — P. 518–523. An investigation has been made of the time dependences of the consumption of ethylbenzene hydroperoxide (EBHP) and the accumulation of its decomposition products in the presence of a complex molybdenum catalyst (CMC). The model obtained includes three routes of hydroperoxide decomposition, taking account of the dependence of the state of the catalyst on the composition of the reaction medium.

Epoxidation and/or hydroxylation of 3-methylbut-1-ene by organic hydroperoxides and hydrogen-peroxide / R. AKHMEDYANOVA, A. LIAKUMOVICH, I. LITVINTSEV, V. SAPUNOV // Petroleum Chemistry. — 1994. — Vol. 34, no. 4. — P. 365–372. An examination has been made of the hydroperoxide and peroxide epoxidation of 3-methylbut-1-ene. The indices of hydroperoxide epoxidation are given. A mathematical model of the production of tert-amyl hydroperoxide by the liquid-phase oxidation of isopentane has been developed. The optimum conditions have been selected for the epoxidation of 3-methylbut-1-ene to the corresponding oxide and diol under interphase catalysis conditions.

BUKOWSKI W., LITVINTSEV I., SAPUNOV V. Kinetics and mechanism of homogeneous catalytic hydroxylation of maleic-acid by hydrogen-peroxide .3. hydrolysis of cis-epoxysuccinic acid with sodium tungstate // Journal of Chemical Technology and Biotechnology. — 1994. — Vol. 61, no. 4. — P. 375–379. The kinetics of catalytic and non-catalytic hydrolysis of cis-epoxysuccinic acid (H(2)E) to tartaric acid (H2T) have been studied. The hydrolysis proceeded much faster in the presence of sodium tungstate catalyst than with an acid or without any catalyst. The results indicated the formation of complexes {cat.H(2)E} between sodium tungstate (cat) and cis-epoxysuccinic acid, presumably in the form of tunstenglycolate of tartaric acid. The reaction has been found to be retarded by tartaric acid or, rather, by its complex with catalyst in the form {cat.2H(2)T}. A mathematical model of the overall process has been developed and the mechanism of reaction discussed. [ DOI ]

BUKOWSKI W., LITVINTSEV I., SAPUNOV V. Kinetics and mechanism of homogeneous catalytic hydroxylation of maleic-acid by hydrogen-peroxide .4. hydrolysis of cis-epoxysuccinic acid in the presence of ferric ions // Journal of Chemical Technology and Biotechnology. — 1994. — Vol. 61, no. 4. — P. 381–386. The kinetics of catalytic and non-catalytic hydrolysis of cis-epoxysuccinic acid have been studied. The hydrolysis leading to tartaric acid has been found to proceed much faster in the presence of iron (III) catalyst than the reaction without a catalyst or with tungstate catalyst. A complex of the form {cat.H(2)E} between iron(III) salts (catalyst) and epoxysuccinic acid seems to be responsible for the main catalytic effect. On the other hand, the reaction has been found to be retarded by the product of hydrolysis, tartaric acid (H2T). The inhibiting effect was caused by the formation of a catalyst deactivating complex in the forms {cat.H2T} and {cat.2H(2)T}. A mathematical model for the overall process has been developed and the mechanism of reaction discussed. [ DOI ]

Study of the kinetics of the catalytic decomposition of ethylbenzene hydroperoxide by the initial rates method / R. AKHMEDYANOVA, I. LITVINTSEV, A. MONAYENKOV, V. SAPUNOV // Petroleum Chemistry. — 1994. — Vol. 34, no. 5. — P. 413–420. An investigation has been made of the kinetic relationships governing the decomposition of ethylbenzene hydroperoxide (EBHP) in the presence of a complex molybdenum catalyst (KMK). Data obtained by processing the curves of product accumulation and EBHP consumption by the initial rates method are given. With account taken of published data and the composition of the products, it is concluded that, at the initial moment, there are two routes by which EBHP decomposition occurs. The presence of molybdenum in low states of oxidation in the KMK has been demonstrated by spectral methods.

Kinetics and mechanism of catalytic hydroxylation of phenol by hydrogen-peroxide .1. general relationships of process variables / I. LITVINTSEV, Y. MITNIK, A. MIKHAILYUK et al. // KINETICS AND CATALYSIS Том: 34 Выпуск: 1 Стр.: 71-75 Часть:. — 1993. — Vol. 34, no. 1. — P. 71–75. Various types of homogeneous catalysts have been investigated to determine their influence on the rate and selectivity of hydroxylation of phenol by hydrogen peroxide. General relationships in the course of the process have been established - relationships that are also characteristic for a number of monosubstituted derivatives of phenol. The influence of initial parameters on the length of the induction period has been investigated, and a mechanism is proposed for the induction period. Ключевые слова.

Kinetics and mechanism of catalytic hydroxylation of phenol by hydrogen-peroxide .2. modeling of / I. LITVINTSEV, Y. MITNIK, A. MIKHAILYUK et al. // Kinetics and Catalysis/ Kinet. Katal. — 1993. — Vol. 34, no. 1. — P. 76–82. A detailed kinetic study has been made of the hydroxylation of phenol by hydrogen peroxide with a previously prepared iron sulfate-pyrocatechol complex as the catalyst. By means of the initial rate method, a model has been obtained, giving an adequate description of all of the observed relationships within the intervals of variation of initial concentrations that were investigated. phenol 0.25-3 M, hydrogen peroxide 0.25-3 M.

Redox kinetics of metal-complexes in nonaqueous solutions - oxidation of a series of tris(1,10-phenanthroline)iron(ii) ions by hexakis(trimethylphosphate)iron(iii) in acetonitrile - a reactivity-selectivity relationship / R. SCHMID, L. HAN, K. KIRCHNER, V. SAPUNOV // Monatshefte f∎r Chemie. — 1993. — Vol. 124, no. 5. — P. 493–509. The kinetics of outer-sphere oxidation of Fe(Xphen)3(2+) ions (X = H or several methyl substituents) in acetonitrile (MeCN) solution by iron(III), introduced as Fe(tmp)6(ClO4)3 (tmp = trimethylphosphate), have been investigated at 25-degrees-C. The reactions are very complex because of solvation equilibria between tmp and MeCN coordinated at Fe3+, with a reduction potential difference of 0.20V for the replacement of one tmp by MeCN. This makes the various solvate species highly different in driving force. The second essential feature is the high charge-type of + 2/ + 3. This brings about strong acceleration by salt because of ion association reducing the work necessary to overcome the Coulombic repulsion in forming the precursor complex. The task was to deconvolute two kinds of speciation: the ionic and the solvate speciations. The analysis suggests the concurrent existence of five Fe(tmp)n3+ (n = 2-6) species among which four species (n=2-5) are reacting, with an additional mono and bis perchlorate ion pair for each n. Extra complications arise as some of the solvation equilibria are not always fast compared to the redox reactions, leading to non-first order rate constants. [ DOI ]

Kinetics and mechanism of homogeneous catalytic hydroxylation of maleic-acid by hydrogen-peroxide .2. analysis of material balance conformities and the mathematical-model / J. OLUDIPE, K. KOIKI, I. LITVINTSEV, V. SAPUNOV // Journal of Chemical Technology and Biotechnology. — 1992. — Vol. 55, no. 24. — P. 103–109. The general kinetic laws relating the changes in reactants and products ratios with changes in the operating conditions of the catalytic epoxidation and hydroxylation reaction of maleic acid by hydrogen peroxide have been analyzed. In the course of the hydroxylation reaction, the formation of epoxysuccinic and tartaric acids, and the decomposition of hydrogen peroxide to molecular oxygen have been observed to take place in parallel. The catalytic complex (Cat.2H-2T) formed between sodium tungstate (catalyst) and tartaric acid in the course of the reaction is found to be inactive in the epoxidation reaction but active in the catalysis of the decomposition of hydrogen peroxide. This fact explains the nonformation of tartaric acid at high maleic acid conversion. The mathematical model for the overall process has been developed.

Catalytic-oxidation of monosubstituted phenols by hydrogen-peroxide / Y. MITNIK, D. OLUDIPE, I. LITVINTSEV, V. SAPUNOV // REACTION KINETICS AND CATALYSIS LETTERS. — 1991. — Vol. 43, no. 2. — P. 321–328. Studies of kinetic peculiarities in hydroxylation of phenols by H2O2 in the presence of ferric sulfate have revealed general regularities of this process. A scheme of this process is suggested accounting for the stepwise conversion of Fe3+ into various complex forms. The reaction is suggested to take place in the coordination sphere of Fe3+. [ DOI ]

Kinetics and mechanism of homogeneous catalytic hydroxylation of maleic-acid by hydrogen-peroxide .1. formal kinetics / J. OLUDIPE, K. KOIKI, L. I. IY,  SAPUNOV // JOURNAL OF CHEMICAL TECHNOLOGY AND BIOTECHNOLOGY Том: 47 Выпуск: 2 Стр.: 151-159. — 1990. — Vol. 47, no. 2. — P. 151–158.

SCHMID R., KIRCHNER K., SAPUNOV V. Redox kinetics of metal-complexes in nonaqueous solutions - oxidation of methyl-substituted tris(1,10-phenanthroline)iron(ii) complexes by hexakis(n,n-dimethylformamide)iron(iii) in acetonitrile // Inorganic Chemistry. — 1989. — Vol. 28, no. 22. — P. 4167–4171. [ DOI ]

BAEVSKII M., LITVINTSEV I., SAPUNOV V. Kinetics and mechanism of the liquid-phase oxidation of cyclohexene .4. decomposition of cyclohexenyl hydroperoxide in the presence of bimetallic catalysts // Kinetics and Catalysis. — 1988. — Vol. 29, no. 3. — P. 493–497.

BAEVSKII M., LITVINTSEV I., SAPUNOV V. Kinetics and mechanism of the liquid-phase oxidation of cyclohexene .5. oxidation of cyclohexene in the presence of bimetallic catalysts // Kinetics and Catalysis. — 1988. — Vol. 29, no. 3. — P. 497–501.

LINERT W., SAPUNOV V. The isokinetic relationship .9. connections to linear free-energy relationships // Chemical Physics. — 1988. — Vol. 119, no. 2. — P. 265–274.

Cyclization of cyclohexanone 4-pyridylhydrazone in the presence of sodium ethylate / D. PLUTITSKII, Y. SMUSHKEVICH, S. MULYASHOV et al. // ZHURNAL ORGANICHESKOI KHIMII. — 1987. — Vol. 23, no. 1. — P. 220–224.

Epichlorohydrin hydrolysis kinetics in aqueous acetic-acid / A. EGORENKOV, I. DOLUDA, I. LITVINTSEV et al. // JOURNAL OF APPLIED CHEMISTRY OF THE USSR. — 1987. — Vol. 60, no. 11. — P. 2423–2424.

KARDASHINA L., Sapunov V. Major kinetic features of the formation of the pi-complex of cobalt hydrocarbonyl with olefin and its conversion to r'co(co)4 // Kinetics and Catalysis. — 1986. — Vol. 27, no. 2. — P. 267–272.

Mechanism of the reaction of polyglycidyl methacrylate with carboxylic-acids / V. KORSHAK, V. SAPUNOV, P. VOSKANYAN et al. // VYSOKOMOLEKULYARNYE SOEDINENIYA SERIYA A. — 1986. — Vol. 28, no. 3. — P. 525–530.

Effect of polyethylene-glycol and crown-ether additives on the decomposition of cyclohexenyl hydroperoxide in the presence of vanadyl acetylacetonate / A. ARTEMOV, I. LITVINTSEV, M. BAEVSKI et al. // Kinetics and Catalysis. — 1985. — Vol. 26, no. 3. — P. 541–545.

SCHMID R., SOUKUP R., SAPUNOV V. Redox kinetics of metal-complexes in non-aqueous solutions .13. the ferriin oxidation of aprotic donors in acetonitrile - relationships between donor and reducing capabilities // JOURNAL OF CHEMICAL RESEARCH-S Выпуск: 3 Стр.: 78-79. — 1985. — Vol. 3. — P. 78–79.

Basic relationships in hydroperoxide epoxidation of olefins with catalysis by compounds of v, w, and ti / V. SAPUNOV, V. SHARYKIN, A. LOGVINOV et al. // Kinetics and Catalysis. — 1983. — Vol. 24, no. 3. — P. 494–498. BASIC RELATIONSHIPS IN HYDROPEROXIDE EPOXIDATION OF OLEFINS WITH CATALYSIS BY COMPOUNDS OF V, W, AND TI.

Epoxidation of cyclohexene by ethylbenzene hydroperoxide in the presence of vanadium catalysts / V. SAPUNOV, V. SHARYKIN, I. LITVINTSEV, N. LEBEDEV // Kinetics and Catalysis. — 1983. — Vol. 24, no. 4. — P. 722–728. EPOXIDATION OF CYCLOHEXENE BY ETHYLBENZENE HYDROPEROXIDE IN THE PRESENCE OF VANADIUM CATALYSTS.

Epoxidation of cyclohexene by ethylbenzene hydroperoxide in the presence of vanadium catalysts / V. SAPUNOV, V. SHARYKIN, I. LITVINTSEV, N. LEBEDEV // Kinetics and Catalysis. — 1983. — Vol. 24, no. 4. — P. 722–726. EPOXIDATION OF CYCLOHEXENE BY ETHYLBENZENE HYDROPEROXIDE IN THE PRESENCE OF VANADIUM CATALYSTS.

KRYLOV I., LITVINTSEV I., SAPUNOV V. Kinetics and mechanism of the liquid-phase oxidation of cyclohexene .3. combined catalysis by cobalt and molybdenum // Kinetics and Catalysis. — 1983. — Vol. 24, no. 1. — P. 37–42. COMBINED CATALYSIS BY COBALT AND MOLYBDENUM COMPOUNDS.

Kinetics and mechanism of the liquid-phase oxidation of cyclohexene .1. epoxidation of cyclohexene by cyclohexenyl hydroperoxide / I. KRYLOV, I. LITVINTSEV, V. SAPUNOV, N. LEBEDEV // Kinetics and Catalysis. — 1982. — Vol. 23, no. 4. — P. 717–721.

Kinetics and mechanism of the liquid-phase oxidation of cyclohexene .2. liquid-phase oxidation of cyclohexene by molecular-oxygen / I. KRYLOV, M. BAEVSKII, I. LITVINTSEV et al. // Kinetics and Catalysis. — 1982. — Vol. 23, no. 4. — P. 721–726. .........

Kinetics and mechanism of the oxinate transfer from thallium(iii)oxinate to iron(iii) in propylenecarbonate / R. SOUKUP, V. SAPUNOV, H. ATESHYKASHI, R. SCHMID // Monatshefte f∎r Chemie. — 1982. — Vol. 113, no. 10. — P. 1093–1105.

Redox kinetics of metal-complexes in non-aqueous solution .11. the iron(ii)-reduction of thallium(iii) oxinate in poorly coordinating solvents / R. SOUKUP, V. SAPUNOV, H. ATESHYKASHI, R. SCHMID // Monatshefte f∎r Chemie. — 1982. — Vol. 113, no. 12. — P. 1349–1366.

Redox kinetics of metal-complexes in non-aqueous solutions .10. temperature-dependence of the iron(ii) reduction of some tris-(oxinato)manganese(iii) complexes in propylenecarbonate and acetonitrile - relations between the arrhenius and the hammett plots / R. SCHMID, R. SOUKUP, V. SAPUNOV, W. LINERT // ZEITSCHRIFT FUR PHYSIKALISCHE CHEMIE. — 1981. — Vol. 126, no. 1. — P. 25–40.

Kinetics and mechanism of the epoxidation of low-molecular cis-butadiene rubber by tert-butyl hydroperoxide / N. KOSHEL, V. SAPUNOV, B. TUROV et al. // VYSOKOMOLEKULYARNYE SOEDINENIYA SERIYA A. — 1980. — Vol. 22, no. 11. — P. 2411–2415.

Sapunov V. Metal-catalyzed epoxidation with hydrogen peroxides // Journal of Molecular Catalysis. — 1980. — Vol. 7, no. 11. — P. 149–158. [ DOI ]

Redox kinetics of metal-complexes in non-aqueous solutions .7. reduction of tris-(5-cyano-8-hydroxyquinolinato)manganese(iii) with iron(ii) in acetonitrile / R. SOUKUP, V. SAPUNOV, R. SCHMID, V. GUTMANN // ZEITSCHRIFT FUR PHYSIKALISCHE CHEMIE. — 1980. — Vol. 119, no. 2. — P. 129–137.

Redox kinetics of metal-complexes in non-aqueous solutions .8. reduction of tris-(5-cyano-8-hydroxyquinolinato)manganese(iii) with iron(ii) in propanediol-1,2-carbonate / R. SOUKUP, V. SAPUNOV, R. SCHMID, V. GUTMANN // ZEITSCHRIFT FUR PHYSIKALISCHE CHEMIE. — 1980. — Vol. 119, no. 2. — P. 139–146.

Redox kinetics of metal-complexes in non-aqueous solutions .9. substituent effect in reduction of manganese(iii) oxinates with iron(ii) in propanediol-1,2-carbonate and acetonitrile / R. SOUKUP, V. SAPUNOV, R. SCHMID, V. nGUTMANN // ZEITSCHRIFT FUR PHYSIKALISCHE CHEMIE. — 1980. — Vol. 119, no. 2. — P. 147–158.

SCHMID R., SAPUNOV V. Kinetics and mechanism of acetylacetonate transfer from acetylacetonatomanganese(iii) to iron(iii) in acetonitrile catalysis and inhibition effects // International Journal of Chemical Kinetics. — 1979. — Vol. 11, no. 1. — P. 1–9. [ DOI ]

Schmid R., Sapunov V. Redox kinetics of metal-complexes in non-aqueous solutions .5. kinetics and mechanism of the iron(ii) reduction of the acetylacetonates of manganese(iii) and cobalt(iii) in acetonitrile // International Journal of Chemical Kinetics. — 1979. — Vol. 11, no. 7. — P. 741–756.

SAPUNOV V., LEBEDEV N. Characteristics of the variation of delta-h-not-equal in the catalytic decomposition of organic hydroperoxides // Kinetics and Catalysis. — 1978. — Vol. 19, no. 4. — P. 874–875. CHARACTERISTICS OF THE VARIATION OF DELTA-H-NOT-EQUAL IN THE CATALYTIC DECOMPOSITION OF ORGANIC HYDROPEROXIDES.

Effects of solvents on polymerization of alpha-oxides / I. KOZLOVA, A. ZHOMOV, V. SAPUNOV, T. BUDKOVA // INTERNATIONAL CHEMICAL ENGINEERING. — 1978. — Vol. 18, no. 1. — P. 88–89. EFFECTS OF SOLVENTS ON POLYMERIZATION OF ALPHA-OXIDES.

Epoxidation of cyclohexene by ethylbenzene hydroperoxide in the presence of molybdenum catalysts .10. catalysis by a molybdenum complex / V. SAPUNOV, I. LITVINTSEV, T. AVAKYAN et al. // Kinetics and Catalysis. — 1978. — Vol. 19, no. 6. — P. 1198–1202. EPOXIDATION OF CYCLOHEXENE BY ETHYLBENZENE HYDROPEROXIDE IN THE PRESENCE OF MOLYBDENUM CATALYSTS .10. CATALYSIS BY A MOLYBDENUM COMPLEX.

Epoxidation of cyclohexene by ethylbenzene hydroperoxide in the presence of molybdenum catalysts .11. inhibition / V. SAPUNOV, I. LITVINTSEV, T. AVAKYAN et al. // Kinetics and Catalysis. — 1978. — Vol. 19, no. 6. — P. 1203–1206. EPOXIDATION OF CYCLOHEXENE BY ETHYLBENZENE HYDROPEROXIDE IN THE PRESENCE OF MOLYBDENUM CATALYSTS .11. INHIBITION OF THE PROCESS BY ALKALI AND ALKALINE-EARTH METALS.

SAPUNOV V., LEBEDEV K. A., NN. Variation of the valences of transition-metals during catalytic decomposition of hydroperoxides // Kinetics and Catalysis. — 1978. — Vol. 19, no. 4. — P. 873–974.

SAPUNOV V., LITVINTSEV I., LEBEDEV N. Epoxidation of cyclohexene by ethylbenzene hydroperoxide in presence of molybdenum catalyst .6. catalysis by molybdenum hexacarbonyl // Kinetics and Catalysis. — 1977. — Vol. 18, no. 3. — P. 521–525.

Epoxidation of cyclohexene by ethylbenzene hydroperoxide in presence of molybdenum catalyst .7. catalysis by carbonyl-complexes of molybdenum / V. SAPUNOV, I. LITVINTSEV, G. MAGOMEDOV, I. MARGITFALVI // Kinetics and Catalysis. — 1977. — Vol. 18, no. 3. — P. 525–529. EPOXIDATION OF CYCLOHEXENE BY ETHYLBENZENE HYDROPEROXIDE IN PRESENCE OF MOLYBDENUM CATALYST .7. CATALYSIS BY CARBONYL-COMPLEXES OF MOLYBDENUM.

Epoxidation of cyclohexene with ethylbenzene hydroperoxide in presence of a molybdenum catalyst .5. transformations / V. SAPUNOV, I. LITVINTSEV, R. SVITYCH, N. RZHEVSKAYA // Kinetics and Catalysis. — 1977. — Vol. 18, no. 2. — P. 348–351. EPOXIDATION OF CYCLOHEXENE WITH ETHYLBENZENE HYDROPEROXIDE IN PRESENCE OF A MOLYBDENUM CATALYST .5. TRANSFORMATIONS OF MOLYBDENUM HEXACARBONYL DURING PROCESS.

Redox kinetics of metal-complexes in non-aqueous solutions .4. oxidation of iron(ii) solvates by iron(iii) in acetonitrile and propanediol-1,2-carbonate / R. SCHMID, V. SAPUNOV, R. KRIST et al. // Inorganica Chimica Acta. — 1977. — Vol. 24, no. 11. — P. 25–29. The oxidation of iron(U) solvates by Fe(phen)p in acetonitrile (An) and propanediolcarbonate (PDC) proceeds via the same reaction scheme as the reduction of iron(III) solvates by Fe(tetramethylphen):: Solutions of iron(H) solvates in these solvents contain not only FeLg, but also complexes of lower coordination number. The lower the coordination number the faster the oxidation of the iron species. In An an intermediate is formed between the pentacoordinated solvate and Fe(phen)? which is obviously stabilized by the solvent. [ DOI ]

SCHMID R., SAPUNOV V., GUTMANN v. Redox kinetics of metal-complexes in non-aqueous solutions .1. reduction of [fe(oh2)6]3+ with fe(ii) in nitromethane, acetonitrile, and dihydroxypropane-1,2-carbonate // BERICHTE DER BUNSEN-GESELLSCHAFT-PHYSICAL CHEMISTRY CHEMICAL PHYSICS. — 1976. — Vol. 80, no. 5. — P. 456–461.

SCHMId R., SAPUNOV V., GUTMANN V. Redox-kinetics of metal-complexes in non-aqueous solutions .2. reduction of some fe(iii)-solvates with fe(ii) in acetonitrile // BERICHTE DER BUNSEN-GESELLSCHAFT-PHYSICAL CHEMISTRY CHEMICAL PHYSICS. — 1976. — Vol. 80, no. 12. — P. 1302–1307.

SCHMID R., SAPUNOV V., GUTMANN V. Redox-kinetics of metal-complexes in non-aqueous solutions .3. reduction of some fe(iii)-solvates with fe(ii) in nitromethane and propanediol-1,2-carbonate // BERICHTE DER BUNSEN-GESELLSCHAFT-PHYSICAL CHEMISTRY CHEMICAL PHYSICS. — 1976. — Vol. 80, no. 12. — P. 1307–1309.

Kinetics of reaction of co3+ with br- in acetic-acid / V. SAPUNOV, L. ABDENNUR, D. MODI et al. // Kinetics and Catalysis. — 1975. — Vol. 16, no. 5. — P. 1144–1145.

SAPUNOV V., SALYUTINA E., LEBEDEV N. Reactions of hydroperoxides .3. decomposition kinetics of ethyl benzene hydroperoxide in presence of a cobalt bromide catalyst // Kinetics and Catalysis. — 1975. — Vol. 16, no. 4. — P. 758–760. REACTIONS OF HYDROPEROXIDES .3. DECOMPOSITION KINETICS OF ETHYL BENZENE HYDROPEROXIDE IN PRESENCE OF A COBALT BROMIDE CATALYST.

Последовательность образования продуктов окисления толуола с кобальт-бромидным катализатором в уксусной кислоте / Э. Ф. Селютина, Н. Г. Дигуров, В. Н. Сапунов, М. Г. Макаров // Труды МХТИ им. Д.И.Менделеева. — 1972. — Т. 70. — С. 43–46.

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