Bifunctional AgOAc/ThioClickFerrophos complex-catalyzed asymmetric 1,3-dipolar cycloaddition of azomethine ylides with aryl- and alkylidene malonates

AgOAc/ThioClickFerrophos complex-catalyzed 1,3-dipolar cycloaddition of glycine imino ester, the precursor of azomethine ylide, with aryl- and alkylidene malonates afforded the corresponding exo-cycloadducts, that is, proline ester derivatives in high yields with high enantiomeric excess (up to 99% ee). The reactions proceeded smoothly under base-free conditions demonstrating the bifunctional catalysis of the silver complex. (C) 2014 Elsevier Ltd. All rights reserved.