Selective Ethylene Trimerization by Titanium Complexes Bearing Phenoxy-Imine Ligands: NMR and EPR Spectroscopic Studies of the Reaction Intermediates | Sciact - CRIS-система Института катализа

Selective Ethylene Trimerization by Titanium Complexes Bearing Phenoxy-Imine Ligands: NMR and EPR Spectroscopic Studies of the Reaction Intermediates Научная публикация

Журнал

Organometallics
ISSN: 0276-7333 , E-ISSN: 1520-6041

Вых. Данные

Год: 2014, Том: 33, Номер: 6, Страницы: 1431-1439 Страниц : 9 DOI: 10.1021/om500017r

Ключевые слова

Catalysts; Chemical reactions; Chlorine compounds; Ethylene; Ligands; Spectroscopic analysis

Авторы

Soshnikov Igor E. ^1,2 , Semikolenova Nina V. ¹ , Ma Jing ³ , Zhao Ke-Qing ³ , Zakharov Vladimir A. ^1,2 , Bryliakov Konstantin P. ^1,2 , Redshaw Carl ^3,4 , Talsi Evgenii P. ^1,2

Организации

1	Boreskov Institute of Catalysis, Pr. Lavrentieva 5, Novosibirsk 630090, Russian Federation
2	Novosibirsk State University, Pirogova 2, Novosibirsk 630090, Russian Federation
3	College of Chemistry and Materials Science, Sichuan Normal University, Chengdu 610066, People’s Republic of China
4	Department of Chemistry, The University of Hull, Cottingham Rd, Hull HU6 7RX, United Kingdom

Информация о финансировании (4)

1	Sichuan Normal University, College of Chemistry and Materials Science
2	Российский фонд фундаментальных исследований	14-03-31155
3	Российский фонд фундаментальных исследований	14-03-91153
4	National Natural Science Foundation of China	21211120163

The catalyst systems (FI)TiCl3/MAO (FI = phenoxyimine ligand with an additional aryl–O–CH3 donor) display exceptionally high activity in selective ethylene trimerization. By means of NMR and EPR spectroscopy, the nature of the Ti species formed in the catalyst systems (FI)TiCl3/MAO, (FI)TiCl3/MMAO, and (FI)TiCl3/AlR3/[Ph3C]+[B(C6F5)4]− (R = Me, Et, iBu) has been studied. It was shown that outer-sphere ion pairs of the type [(FI)TiIVMe2]+[A]− ([A]− = [MeMAO]−, [MeMMAO]−, [B(C6F5)4]−) are formed at the initial stage of the reaction of (FI)TiCl3 with MAO, MMAO, and AlMe3/[Ph3C]+[B(C6F5)4]−. These ion pairs further partially convert into TiIII and TiII species. In the systems (FI)TiCl3/MAO and (FI)TiCl3/AlMe3/[Ph3C]+[B(C6F5)4]−, complexes with the proposed structures (FI)TiIIIMe2, (FI)TiIICl, and [(FI)TiII(S)]+[A]− ([A]− = [MeMAO]−, [B(C6F5)4)]−, S = solvent, vacancy) were observed (concentrations of TiIII species was lower than those of the TiII congeners). In contrast, in the system (FI)TiCl3/MMAO, the concentrations of TiIII species (ion pairs of the type [(FI)TiIII(μ-H)(μ-Cl)AliBu2]+[MeMMAO]−) were higher than those of the TiII counterparts (ion pairs [(FI)TiII(S)]+[MeMMAO]−). The system (FI)TiCl3/MMAO displays lower activity and selectivity in 1-hexene formation, in comparison to (FI)TiCl3/MAO, due to undesirable PE generation. Probably, TiII and TiIV ion pairs are those participating in ethylene trimerization.

Soshnikov I.E. , Semikolenova N.V. , Ma J. , Zhao K-Q. , Zakharov V.A. , Bryliakov K.P. , Redshaw C. , Talsi E.P.
Selective Ethylene Trimerization by Titanium Complexes Bearing Phenoxy-Imine Ligands: NMR and EPR Spectroscopic Studies of the Reaction Intermediates

Organometallics. 2014. V.33. N6. P.1431-1439. DOI: 10.1021/om500017r WOS Scopus РИНЦ CAPlusCA OpenAlex

Полный текст от издателя

Поступила в редакцию:	8 янв. 2014 г.
Опубликована online:	12 мар. 2014 г.
Опубликована в печати:	24 мар. 2014 г.

Web of science:	WOS:000333478400015
Scopus:	2-s2.0-84896986178
РИНЦ:	21869255
Chemical Abstracts:	2014:397655
Chemical Abstracts (print):	160:458012
OpenAlex:	W2330559276

БД	Цитирований
Web of science	15
Scopus	19
РИНЦ	19
OpenAlex	20