Reactivity of bis(alkene) tetracarbonyl complexes of tungsten: evidence for alkene to π-allyl hydride rearrangement

Autor:	Józef J. Ziółkowski, M. Jaroszewski, Teresa Szymańska-Buzar, Michal Wilgocki
Rok vydání:	1996
Předmět:	chemistry.chemical_classification Olefin fiber Hydride Chemistry Alkene Process Chemistry and Technology Photochemistry Metathesis Catalysis Polymer chemistry Reactivity (chemistry) Lewis acids and bases Physical and Theoretical Chemistry Isomerization
Zdroj:	Journal of Molecular Catalysis A: Chemical. 112:203-210
ISSN:	1381-1169
DOI:	10.1016/1381-1169(96)00124-0
Popis:	The bis(alkene)tetracarbonyl complexes of tungsten were identified as olefin isomerization and metathesis catalyst precursors whose activities are based on the formation of a π-allyl hydride intermediate. It has been observed that the β-hydrogen atom of coordinated olefin may migrate to the metal giving η3-allylic hydrides which have been characterized by their 1H NMR spectra. This is the first case where the rearrangement of tungsten(0) alkenes coordinated to a π-allylic hydrides intermediate, fundamental to many catalytic mechanisms, can be observed directly. In the presence of Lewis acid the same alkene complexes are catalytically active toward olefin metathesis. It seems reasonable that the catalystically active alkylidene compounds are formed from the coordinated alkene via π-allylic hydride and metallacyclobutane precursors.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::de822650888b7b26589ee7169820f5ea https://doi.org/10.1016/1381-1169(96)00124-0 Zobrazit plný text záznamu Full Text from ScienceDirect