Ab Initio Calculations of Propylene Addition to the Metal-Methyl Bond in Titanium and Aluminum Alkyl Complexes Научная публикация
Журнал |
Kinetics and Catalysis
ISSN: 0023-1584 , E-ISSN: 1608-3210 |
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Вых. Данные | Год: 1997, Том: 38, Номер: 2, Страницы: 231-235 Страниц : 5 | ||
Ключевые слова | OLEFIN POLYMERIZATION; ETHYLENE | ||
Авторы |
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Организации |
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Реферат:
The reaction of propylene addition to the aluminum-methyl and titanium-methyl bonds in the H2AlCH3 and H2TiCH3 complexes has been examined by the ab initio SCF MO LCAO method in the valence-split Gaussian basis set. The structures of the transition state (TS) of the insertion reaction, the heats of the pi-complex formation, and the activation energies for the insertion of the coordinated propylene via the mechanisms of 1,2- and 2,1-cis-insertion were calculated. It is shown that a lower value of the free activation energy of the 1,2-addition in comparison with that of the 2,1-addition is determined by lower values of both the activation energy and entropy. It is suggested that the driving force for 1,2-insertion is the polarization of the C=C bond in propylene, due to which the electrostatic interaction in the four-center transition state stabilizes TS-1,2 more strongly than TS-2,1. The calculated results indicate that propylene is characterized by a decrease in reactivity (as compared to ethylene) in the reaction of addition to the M-R bond. This fact may be attributed to a higher position of the pi* orbital of propylene (the stronger pi bond) as compared to ethylene. It is shown that the energy of the antibonding pi* orbital of monomers (acetylene, ethylene, and propylene) can serve as a reactivity index for the reaction of addition to the metal-alkyl bond.
Библиографическая ссылка:
Zakharov I.I.
, Zakharov V.A.
, Zhidomirov G.M.
Ab Initio Calculations of Propylene Addition to the Metal-Methyl Bond in Titanium and Aluminum Alkyl Complexes
Kinetics and Catalysis. 1997. V.38. N2. P.231-235. WOS Scopus РИНЦ
Ab Initio Calculations of Propylene Addition to the Metal-Methyl Bond in Titanium and Aluminum Alkyl Complexes
Kinetics and Catalysis. 1997. V.38. N2. P.231-235. WOS Scopus РИНЦ
Оригинальная:
Захаров И.И.
, Захаров В.А.
, Жидомиров Г.М.
Неэмпирические расчеты реакции присоединения пропилена по связи металл-метил в алкильных комплексах титана и алюминия
Кинетика и катализ. 1997. Т.38. №2. С.254-258. РИНЦ
Неэмпирические расчеты реакции присоединения пропилена по связи металл-метил в алкильных комплексах титана и алюминия
Кинетика и катализ. 1997. Т.38. №2. С.254-258. РИНЦ
Даты:
Поступила в редакцию: | 3 нояб. 1995 г. |
Идентификаторы БД:
Web of science | WOS:A1997WW73300011 |
Scopus | 2-s2.0-0642333142 |
РИНЦ | 13263147 |
Chemical Abstracts | 1997:289236 |
Chemical Abstracts (print) | 126:317705 |
Цитирование в БД:
Пока нет цитирований