|
ИСТИНА |
Войти в систему Регистрация |
ИСТИНА ИНХС РАН |
||
Multisubstituted C2-symmetric ansa-metallocenes bearing nitrogen heterocycles: influence of substituents on catalytic properties in propylene polymerization at higher temperaturesстатья
Статья опубликована в высокорейтинговом журнале
Информация о цитировании статьи получена из
Web of Science,
Scopus
Статья опубликована в журнале из списка Web of Science и/или Scopus
Дата последнего поиска статьи во внешних источниках: 17 июня 2021 г.
- Авторы: Kulyabin Pavel S., Izmer Vyatcheslav V., Goryunov Georgy P., Sharikov Mikhail I., Kononovich Dmitry S., Uborsky Dmitry V., Canich Jo Ann M., Voskoboynikov Alexander Z.
- Журнал: Dalton Transactions
- Том: 50
- Год издания: 2021
- Издательство: Royal Society of Chemistry
- Местоположение издательства: United Kingdom
- Первая страница: 6170
- Последняя страница: 6180
- DOI: 10.1039/d1dt00645b
- Аннотация: In this work we systematically studied the effects of modifications of substituents on the performance of the isospecific zirconocene-based catalyst family, Me2Si(2-Alk-4-(N-carbazolyl)Ind)ZrX2 (X = Cl, Me), wherein the progenitor was shown to be particularly suitable in high-temperature propylene polymerization processes. In order to obtain the required zirconocenes, we developed a novel synthetic pathway to 4-(N-carbazolyl)indenes through Pd-catalyzed cyclizations of 2,2′-dibromobiaryls with 4-aminoindenes, which were synthesized via Buchwald–Hartwig reaction or electrophilic amination of 4-indenyl Grignard reagents with trimethylsilylmethyl azide. By a number of examples, the anion-promoted rac-to-meso isomerization method was shown to work reliably well for preparation of rac-ZrMe2-complexes. Certain zirconocenes among the 21 tested in propylene polymerization at 70 and 100 °C under MAO or borate activation outperformed the parent catalyst in molecular weight capability, regio- or stereoselectivity.
- Добавил в систему: Уборский Дмитрий Вадимович