Development of Bifunctional N-Heterocyclic Carbene Ligands

Abstract

Cooperative catalysis enabling simultaneous activation of both an electrophile and a nucleophile has emerged as a powerful strategy in organic synthesis. We envision that imidazo[1,5-a]pyridine-derived N-heterocyclic carbene (ImPy) ligands will provide a convenient framework where a various functional group can be easily implemented to make bifunctional N-heterocyclic carbene ligands. Several transition metal complexes containing imidazopyridinylidene carbene (ImPy) ligands have been prepared. The ImPy-Cu(I) complexes efficiently catalyzed the direct C-H carboxylation of benzoxazole with CO2. ImPy-Pd catalysts exhibited good reactivity in Buchwald-Hartwig amination reactions. Current progress on design of new bifunctional ImPy transition metal catalysts will be discussed in details in the presentation.