sulfinimines 1c-g derivedfromaliphaticaldehydes with TMSCN in the presence of CsF gave alpha-amino nitriles in high diastereoselectivity and yield. alpha,beta-Diamino acid derivatives were also obtained in high diastereoselectivity from the reaction of 2-aziridinesulfinimines 1h and 1i followed by ring-opening of the products with thiophenol. The presence of hydrogen at the alpha-position of the C=N double