The use of enantiomerically pure N-sulfinimines in asymmetric Baylis–Hillman reactions

The electrophilic behaviour of enantiomerically pure N-p-toluenesulfinimines (1a–d) and N-tert-butanesulfinimine 2 has been tested in the asymmetric Baylis–Hillman reaction with methyl acrylate with and without Lewis acids. In the presence of In(OTf)3 good yields and high diastereoselectivities have been achieved providing an effective route to β-amino-α-methylene esters.