Asymmetric addition of dialkyl phosphite and diamido phosphite anions to chiral, enantiopure sulfinimines: A new, convenient route to enantiomeric α-aminophosphonic acids

Article abstract of DOI:10.1016/S0957-4166(97)00606-X

Lithium or sodium dialkyl phosphites and diamido phosphites 3 undergo addition to (+)-(S)-benzylidene-p-toluenesulfinamide 2 affording N-sulfinyl-α-aminophosphonates 4 in a diastereoisomeric ratio from 63:37 to 94:6. The major diastereoisomers formed in addition of lithium dimethyl phosphite 3a and lithium bis-diethylamido phosphite 3e to (+)-(S)-2 were separated and converted into enantiopure (+)-(R)- and (-)-(S)-α-aminobenzyl phosphonic acids 5, respectively.