N-Cyclopropenio-imidazol-2-ylidene: An N-heterocyclic carbene bearing an N-cationic substituent

Abstract

A cationic NHC 1⁺ bearing an N-bound 2,3-bis(diisopropylamino)cyclopropenium group is reported. From an easily available dicationic imidazolium precursor, the coordination abilities and stereo-electronic properties of 1⁺ are evaluated by the formation of Pd(II), Rh(I) and Au(I) complexes. The cationic gold(I) complex is implemented in representative intramolecular Au(I)-catalyzed cyclizations.