Covalent bidentate ligand-enabled regioselective Wacker-type oxidation of olefins

Abstract

The utilization of Pd(II)-catalyzed oxidation for the transformation of terminal olefins into methyl ketones has emerged as a particularly intriguing and versatile strategy in organic synthesis. Herein we report a novel Pd(II)-catalyzed Wacker-type oxidation with covalent bidentate ligands. The ligand, 1-(pyridin-2-yl)-1,2-dihydro-3H-indazol-3-one, exhibits excellent performance in converting olefins to ketones. The optimized reaction conditions include the use of TBHP as oxidant, EtOH or MeCN as solvent and short reaction time. The substrate scope includes various substituted olefins, which undergo the desired oxidation reaction with high efficiency.