This work was supported by the National Institute of General Medical Sciences (NIGMS 1R01M079644).
Migratory Decarboxylative Coupling of Coumarins: Synthetic and Mechanistic Aspects†
Article first published online: 19 APR 2011
Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Angewandte Chemie International Edition
Volume 50, Issue 22, pages 5157–5161, May 23, 2011
How to Cite
Jana, R., Partridge, J. J. and Tunge, J. A. (2011), Migratory Decarboxylative Coupling of Coumarins: Synthetic and Mechanistic Aspects. Angew. Chem. Int. Ed., 50: 5157–5161. doi: 10.1002/anie.201100765
- Issue published online: 16 MAY 2011
- Article first published online: 19 APR 2011
- Manuscript Revised: 3 MAR 2011
- Manuscript Received: 29 JAN 2011
- National Institute of General Medical Sciences. Grant Number: NIGMS 1R01M079644
- decarboxylative coupling;
On the move: Decarboxylative coupling of allyl 4-methyl-3-carboxycoumarins provides the products of γ-allylation of the methyl group rather than the typical regiospecific α-allylation. Mechanistic studies show that intramolecular proton transfer from the 4-methyl group to the 3-carboxylate allows allylation of the remote methyl group. The resulting 4-butenyl-3-carboxyl coumarin undergoes Pd0-catalyzed decarboxylation to provide the observed products (see scheme).