Ni(II)-catalyzed C-H hydroarylation of diarylacetylenes with imidazolium salts.

A simple Ni(II)-catalyzed C-H hydroarylation of diarylacetylenes with imidazolium salts without adding any ligand was developed. It provides a facile and efficient access to ( E )-2-(1,2-diarylvinyl)imidazolium salts. The preliminary results indicate a rare nonredox catalytic cycle of Ni(II), complementary to the common redox catalytic cycle starting from Ni(0).