Stereoselective bis-functionalizations of arene chromium tricarbonyl complexes via brook rearrangements.

[reaction: see text] An efficient method has been developed for the stereoselective bis-functionalization of arene chromium tricarbonyl complexes. Initial nucleophilic addition of organolithium reagents to a carbonyl moiety is followed by a 1,4-carbon to oxygen silyl migration (Brook rearrangement) and alkylation of the resultant aryl anion.