Catalyst‐Dependent Stereospecific [3,3]‐Sigmatropic Rearrangement of Sulfoxide‐Ynamides: Divergent Synthesis of Chiral Medium‐Sized N,S‐Heterocycles

Abstract Medium‐sized N , S ‐heterocycles have received tremendous interest due to their biological activities and potential medical applications. However, asymmetric synthesis of these compounds are extremely rare. Described herein is a catalyst‐dependent [3,3]‐sigmatropic rearrangement of sulfoxide‐ynamides, enabling divergent and atom‐economic synthesis of a series of valuable medium‐sized N , S ‐heterocycles in moderate to good yields with broad substrate scope. Importantly, excellent enantioselectivities have been achieved via an unprecedented chirality‐transfer. Moreover, theoretical calculations are employed to elucidate the origins of the catalyst‐dependent stereospecific [3,3]‐rearrangement.