Vijaykumar M, Punji B. Pd(II)-Catalyzed Chemoselective Acetoxylation of C(sp
2)-H and C(sp
3)-H Bonds in Tertiary Amides.
J Org Chem 2021;
86:8172-8181. [PMID:
34038129 DOI:
10.1021/acs.joc.1c00629]
[Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Palladium-catalyzed chemoselective C(sp2)-H and C(sp3)-H acetoxylation of synthetically useful tertiary amides is reported under relatively mild reaction conditions. This protocol proceeds through the assistance of a weakly coordinated directing group (C═O) and requires low catalyst (1.0 mol %) loading. Diverse functionalities, such as C(sp2)-Cl, C(sp3)-Cl, -CF3, -COOEt, and -NO2 groups, including morpholinyl, piperazinyl, and pyrrolidinyl heterocycles, are compatible under the reaction conditions. Further functionalization of this protocol is demonstrated by hydrolysis to alcohols, alcohol-acids, as well as reduction to tertiary amines. A preliminary kinetic isotope effect study supported the rate-limiting C-H bond activation process.
Collapse