Photocatalytic Aerobic Double Friedel‐Crafts Reaction of Glycine Derivatives with Anilines: An Efficient Synthesis of Diarylmethanes

Abstract

A mild and efficient aerobic double Friedel-Crafts reaction of glycine derivatives with anilines has been developed with the assist of a photocatalytic system involving inexpensive Eosin Y as a photocatalyst. Under the optimized conditions, a range of N-arylglycine derivatives underwent this oxidative coupling reaction smoothly to give the desired diarylmethane derivatives with high para-regioselectivities in moderate to excellent yields. Moreover, mechanistic studies revealed that this transformation followed a radical-mediated pathway. This strategy featured mild conditions, operational simplicity, wide substrate scope and good functional group tolerance. Results and DiscussionTo begin our study, we chose glycine ester 1 a and N,Ndimethylaniline 2 a as model substrates to explore and optimize [a] J.