Ferrocene-based planar chiral imidazopyridinium salts for catalysis

Abstract

Planar chirality remains an underutilized control element in asymmetric catalysis. Factors that have limited its broader application in catalysis include poor catalyst performance and difficulties associated with the economical production of enantiopure planar chiral compounds. The construction of planar chiral azolium salts that incorporate a sterically demanding iron sandwich complex is now reported. Applications of this new N-heterocyclic carbene as both an organocatalyst and a ligand for transition-metal catalysis demonstrate its unprecedented versatility and potential broad utility in asymmetric catalysis.

Keywords: N-heterocyclic carbenes; asymmetric synthesis; organocatalysis; transition-metal catalysis.