Convenient synthesis of chiral non-racemic S-mesityl sulfinimines

A direct multi-component coupling of (2S,4R,5S)-N-tosyl-4-methyl-5-phenyl-1,2,3-oxathiozolidine-2-oxide with mesityl magnesium bromide, LHMDS and a range of aldehydes produces chiral sulfinimines in essentially optically pure form in an operationally simple single pot procedure.