Abstract Chiral N-heterocyclic carbenes (NHCs) mediate the enantioselective addition of 2- phenylphenol to unsymmetrical alkylarylketenes, delivering α-alkyl-α-arylacetic acid derivatives with good levels of enantiocontrol (up to 84% ee). Enantiodivergent stereochemical outcomes are observed using 2-phenylphenol and benzhydrol in the NHC- promoted esterification reaction using a triazolium precatalyst derived from pyroglutamic ...
