The unprecedented selective tetramerisation of ethylene to 1-octene was recently reported. In the present study various mechanistic aspects of this novel transformation were investigated. The unusually high 1-octene selectivity in chromium-catalyzed ethylene tetramerisation reactions is caused by the unique extended metallacyclic mechanism in operation. Both 1-octene and higher 1-alkenes are formed by further ethylene insertion into a metallacycloheptane intermediate, whereas 1-hexene is formed by elimination from this species as in other reported trimerisation reactions. This is supported by deuterium labeling studies, analysis of the molar distribution of 1-alkene products, and identification of secondary co-oligomerization reaction products. In addition, the formation of two C6 cyclic products, methylenecyclopentane and methylcyclopentane, is discussed, and a bimetallic disproportionation mechanism to account for the available data is proposed. © 2005 American Chemical Society.

Item Type:	Refereed Article
Research Division:	Chemical Sciences
Research Group:	Other chemical sciences
Research Field:	Other chemical sciences not elsewhere classified
Objective Division:	Manufacturing
Objective Group:	Industrial chemicals and related products
Objective Field:	Organic industrial chemicals (excl. resins, rubber and plastics)
UTAS Author:	McGuinness, DS (Dr David McGuinness)
ID Code:	46820
Year Published:	2005
Web of Science® Times Cited:	222
Deposited By:	Chemistry
Deposited On:	2007-09-04
Last Modified:	2007-09-04
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