Intermolecular cycloaddition of nonstabilized azomethine ylides generated from 1,3-thiazolidine-4-carboxylic acids: synthesis of 5,7a-dihydro-1H,3H-pyrrolo[1,2-c]thiazoles
作者:Ana L. Cardoso、Agnieszka Kaczor、Artur M.S. Silva、Rui Fausto、Teresa M.V.D. Pinho e Melo、António M. d'A. Rocha Gonsalves
DOI:10.1016/j.tet.2006.08.029
日期:2006.10
The 1,3-dipolar cycloaddition of dimethyl acetylenedicarboxylate with nonstabilized azomethine ylides, generated via the decarboxylative condensation of 1,3-thiazolidine-4-carboxylic acids with aldehydes, afforded 5,7a-dihydro-1H,3H-pyrrolo[1,2-c]thiazole derivatives. 2-Substituted-1,3-thiazolidine-4-carboxylic acids led to the stereoselective formation of 5,7a-dihydro-1H,3H-pyrrolo[1,2-c]thiazoles. Quantum-chemistry calculations were carried out allowing the rationalization of the observed stereoselective formation of the anti-dipole. (c) 2006 Elsevier Ltd. All rights reserved.