Regioselective diarylation of ketone enolates by homogeneous and heterogeneous catalysis: synthesis of triarylethanones

A novel, one-step approach to 1,2,2-triarylethanones is achieved by an efficient palladium-catalyzed α,α-diarylation of commercially available acetophenones. After assaying an array of experimental conditions, two convenient procedures, which avoid ortho-arylation side reactions, are chosen to perform the target regioselective diarylation. The former protocol is based on the use of such a simple homogeneous system as Pd(OAc)2/PPh3/Cs2CO3, and the latter one employs a commercially available polymer-anchored catalyst, FibreCat™ 1026.