Highly diastereoselective addition of lithio vinyl sulfoxides to N-sulfinimines: an entry to enantiopure 3-sulfinyl-2,5-cis-dihydropyrroles.

The addition of enantiopure α-metalated vinyl and dienyl sulfoxides to enantiomerically pure N-sulfinimines takes place with high diastereoselectivity primarily directed by the N-sulfinimine sulfur. The resulting allylic amines have been further transformed into highly functionalized 3-sulfinyl and 3-sulfonyl 2,5-cis-dihydropyrroles by reaction with electrophiles.