Asymmetric synthesis of syn-(2R,3S)- and anti-(2S,3 s)-ethyl diamino-3-phenylpropanoates from N-(benzylidene)-p-toluenesulfinamide and glycine enolates

Addition of differentially N-protected glycine enolates to enantiopure sulfinimines affords syn- and anti-alpha,beta-diamino esters with high diastereoselectivities and good yields.