Palladium catalyzed C–H bond acetoxylation: isoxazolinyl as a directing group†
Abstract
Pd(OAc)2-catalyzed acetoxylations of 3-aryl or 3-alkyl groups mounted on a 2-isoxazoline ring were studied. Ortho-selective C–H bond activation directed by an isoxazolinyl group was realized. 2-Isoxazoline rings without and with one or two alkyl substituents in the 5-position were effective directing groups. The substituent effect on reactivity and regioselectivity was examined. The acetoxylation was applied to the synthesis of useful intermediates.