Conjugate addition of organolithium reagents to α,β-unsaturated carboxylic acids

Abstract

Conjugate addition of primary, secondary, tertiary alkyl and phenyl lithium reagents to 2-alkenoic acids affords good yields of branched saturated carboxylic acids. Substitution by methyl groups at the α-carbon strongly decreases reactivity, whereas deprotonation of the starting acid occurs almost exclusively with methyl substitution at the β-carbon of the 2-alkenoic acid.