Catalytic asymmetric conjugate addition of thiols to α,β-unsaturated thioamides: expeditious access to enantioenriched 1,5-benzothiazepines.

Softly does it: The title reaction proceeded under proton transfer conditions with a catalyst prepared from commercially available reagents to afford the desired product in high enantioselectivity. The reaction was compatible with a free amino group, thus allowing for expeditious access to enantiomerically enriched 1,5-benzothiazepines, which are important chemical entities in medicinal chemistry.