Bis(N-heterocyclic carbene)-borylene-mediated heteroallene activation

Abstract

This study describes a bis(N-heterocyclic carbene)–borylene that activates heteroallenes. The borylene undergoes a bora-Staudinger reaction with azide to afford an NHC–iminoborane, and also catalyzes the cyclotrimerization of isocyanates to give isocyanurates. In the presence of excess pinacolborane, it catalyzes the chemoselective hydroboration of isocyanates to form N-boryl formamides.