Copper-catalyzed asymmetric alkynylation of pyrazole-4,5-diones using chloramphenicol base-derived hydroxyl oxazoline ligands

Abstract

The asymmetric copper-catalyzed alkynylation reactions of pyrazole 4,5-diones in the presence of a hydroxyl oxazoline ligand, which was derived from low cost, easily accessible chloramphenicol base (ANP), are reported. The notable features of this protocol include its mild and base additive free reaction conditions, and broad functional group tolerance.