Palladium catalyzed domino reaction of 1,4-disubstituted 1,2,3-triazoles via double C–H functionalization: one-pot synthesis of triazolo[1,5-f]phenanthridines

Abstract

A palladium catalyzed domino coupling reaction of 1,4-disubstituted triazoles via homocondensation with a second molecule is presented. The domino couplings involve the formation of biaryl and bi(hetero)aryl bonds through a five membered carbopalladacycle intermediate. The approach provides a simple, straight forward and facile route to access triazolo[1,5-f]phenanthridines in high yields. Furthermore, the developed protocol was extended to heterocondensation in the presence of norbornene.