Significant asymmetric amplification in enantioselective Cu/DiPPAM-catalyzed 1,6- and 1,4-conjugate additions of diethylzinc to (di)enones

Magaly Magrez; Joanna Wencel-Delord; Alexandre Alexakis; Christophe Crévisy; Marc Mauduit

doi:10.1021/ol300866p

Significant asymmetric amplification in enantioselective Cu/DiPPAM-catalyzed 1,6- and 1,4-conjugate additions of diethylzinc to (di)enones

Org Lett. 2012 Jul 20;14(14):3576-9. doi: 10.1021/ol300866p. Epub 2012 Jun 28.

Authors

Magaly Magrez¹, Joanna Wencel-Delord, Alexandre Alexakis, Christophe Crévisy, Marc Mauduit

Affiliation

¹ Ecole Nationale Supérieure de Chimie de Rennes , CNRS, UMR 6226, Avenue du Général Leclerc, CS 50837, 35708 Rennes Cedex 7, France, Department of Organic Chemistry, University of Geneva , Quai Ernest Ansermet 30, 1211 Geneva, Switzerland, and Université Européenne de Bretagne , 5 Bd Laënnec, 35000 Rennes, France.

PMID: 22743000
DOI: 10.1021/ol300866p

Abstract

An unprecedented and strong positive nonlinear effect (NLE) was observed in Cu/DiPPAM-catalyzed asymmetric 1,6-conjugate addition of Et2Zn on (E)-3-(prop-1-en-1-yl)cyclohex-2-enone (71% ee reached with a 40% ee ligand). Moreover, similar behaviors were observed in Cu/DiPPAM-catalyzed 1,4-asymmetric conjugate additions of Et2Zn on both cyclohexenone and (E)-3-non-3-en-2-one (83% and 70% ee, respectively, reached with a 40% ee ligand).