Stereochemical control and mechanistic aspects of the alkylation of [(η5-C5H5)Fe(L)(CO)(COCHR)]–Li+(L = PPh3, PPh2NEt2; R = Me, Et): X-ray crystal structure of [(η5-C6H5)Fe(PPh3)(CO){COCH(Me)Et}]

Abstract

Determination of the molecular structure of [(η⁵-C₅H₅)Fe(PPh₃)(CO){COCH(Me)Et}], formed in the diastereoselective methylation of [(η⁵-C₅H₅)Fe(PPh₃)(CO)(COCHEt)]^–Li⁺, allows the assignment of the relative configuration of the new chiral centre and indicates the origin of the high diastereoselectivities observed in this type of reaction.