Influence of intramolecular N–H···O–Ni hydrogen bonding in nickel(II) diphenylphosphinoenolate phenyl complexes on the catalytic oligomerization of ethylene

Abstract

Nickel(II) diphenylphosphinoenolate complexes have been prepared from ( ortho-HX-substituted benzoylmethylene)triphenyl phosphoranes (X = NMe, NPh) and [Ni(1,5-cod) 2] in the presence of a tertiary phosphine (PPh 3 or P( p-C 6H 4F) 3). An X-ray diffraction study of the complexes ▪ 10 and ▪ 16 establishes the presence of strong intramolecular hydrogen bonding between the enolate oxygen and the N–H function, as originally found in ▪ 11. This feature favours the formation of the desired shorter-chain-length products in the catalytic oligomerisation of ethylene. To cite this article: P. Braunstein et al., C. R. Chimie 8 (2005) .