Bicyclic bridgehead phosphoramidite (briphos) ligands with tunable π-acceptor ability and catalytic activity in the rhodium-catalyzed conjugate additions

Abstract

A new type of bicyclic bridgehead phosphoramidites (briphos) is reported, where the geometrical constraints significantly enhance the π- acceptor ability compared with its monocyclic analogs. The briphos is shown to be highly efficient and tunable for Rh(I)-catalyzed conjugate additions of aryl boronic acids to α,β-unsaturated ketones and N-tosyl ketimines.