This work was supported in part by ERATO from JST.
Copper-Catalyzed Intramolecular C(sp3)H and C(sp2)H Amidation by Oxidative Cyclization†
Article first published online: 24 FEB 2014
© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Angewandte Chemie International Edition
Volume 53, Issue 13, pages 3496–3499, March 24, 2014
How to Cite
Wang, Z., Ni, J., Kuninobu, Y. and Kanai, M. (2014), Copper-Catalyzed Intramolecular C(sp3)H and C(sp2)H Amidation by Oxidative Cyclization. Angew. Chem. Int. Ed., 53: 3496–3499. doi: 10.1002/anie.201311105
- Issue published online: 19 MAR 2014
- Article first published online: 24 FEB 2014
- Manuscript Received: 21 DEC 2013
- CH activation;
The first copper-catalyzed intramolecular C(sp3)H and C(sp2)H oxidative amidation has been developed. Using a Cu(OAc)2 catalyst and an Ag2CO3 oxidant in dichloroethane solvent, C(sp3)H amidation proceeded at a terminal methyl group, as well as at the internal benzylic position of an alkyl chain. This reaction has a broad substrate scope, and various β-lactams were obtained in excellent yield, even on gram scale. Use of CuCl2 and Ag2CO3 under an O2 atmosphere in dimethyl sulfoxide, however, leads to 2-indolinone selectively by C(sp2)H amidation. Kinetic isotope effect (KIE) studies indicated that CH bond activation is the rate-determining step. The 5-methoxyquinolyl directing group could be removed by oxidation.