Catalyst-Controlled Multicomponent Aziridination of Chiral Aldehydes.

A highly diastereoselective and enantioselective method for the multicomponent aziridination of chiral aldehydes has been developed with BOROX catalysts of the VANOL (3,3'-diphenyl-2,2'-bi-1-naphthol) and VAPOL (2,2'-diphenyl-(4-biphenanthrol)) ligands. Very high to perfect catalyst control is observed with most all substrates examined including aldehydes with chiral centers in the α- and β-positions. High catalyst control was also observed for a number of chiral heterocyclic aldehydes allowing for the preparation of epoxy aziridines, bis(aziridines) and ethylene diaziridines. Application of this reaction in the synthesis of β -homo-d-alloisoleucine and β -homo-l-isoleucine is reported.