Chiral α-amino phosphonates via rhodium-catalyzed asymmetric 1,4-addition reactions
Nicolas Lefevre1, Jean-Louis Brayer, Benoît Folléas
1Ecole Nationale Supérieure de Chimie de Paris, Laboratoire Charles Friedel (UMR 7223, CNRS), 11 rue Pierre et Marie Curie, 75231 Paris cedex 05, France.
Abstract:
A new approach for the preparation of enantioenriched α-amino phosphonates and derivatives is described. Indeed, the rhodium-catalyzed asymmetric 1,4-addition of potassium organotrifluoroborates to dehydroaminophosphonates afforded α-amino phosphonates in good yields and high enantioselectivities (up to 96%) using Difluorphos as a chiral ligand.
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