A comparative study of seven co-ordinate Mo(II) and W(II) catalysts in the ring opening polymerization of norbornene

Autor:	Michael A. Beckett, Paul K. Baker, Ben M. Stiefvater-Thomas
Rok vydání:	2003
Předmět:	biology Stereochemistry Process Chemistry and Technology Homogeneous catalysis Ring-opening polymerization Medicinal chemistry Catalysis ASPH chemistry.chemical_compound chemistry Polymerization biology.protein Physical and Theoretical Chemistry Acetonitrile Benzene Norbornene
Zdroj:	Journal of Molecular Catalysis A: Chemical. 193:77-81
ISSN:	1381-1169
DOI:	10.1016/s1381-1169(02)00475-2
Popis:	The ring-opening polymerization of norbornene was investigated in refluxing benzene solution with [MI 2 (CO) 3 (L)(L′)] (M = Mo, W; L = L′ = NCCH 3 , PPh 3 , AsPh 3 ; L = NCMe, L′ = PPh 3 , AsPh 3 ) as catalysts. Turnover numbers (TNs) after 20 min ranged from 40 to 380 with the highest value recorded for [WI 2 (CO) 3 (NCMe) 2 ]. Under similar conditions Grubbs’ catalyst, [RuCl 2 (PCy 3 ) 2 (CHPh)], was at least 1000-fold more active. A first order relationship was obtained between the initial polymerization rate and [WI 2 (CO) 3 (NCMe) 2 ] concentration. The catalytic activity of [WI 2 (CO) 3 (NCMe) 2 ] showed exponential decay with t 1/2 =600 s.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::ee2da926562e2baf60fb4dcff7bab659 https://doi.org/10.1016/s1381-1169(02)00475-2 Zobrazit plný text záznamu Full Text from ScienceDirect