Preparation of Benzothiazoles and Heterocyclic Spiro Compounds Through Cu‐catalyzed S−S Bond Cleavage and C−S Bond Formation

Abstract The reaction of 2,2'‐dithiobis(benzenamine)s with various aldehydes in the presence of CuOAc catalyst under air without any additives afforded the corresponding benzothiazoles. When cycloalkylcarbaldehydes were reacted under similar conditions, benzothiazoles and heterocyclic spiro compounds were produced. Gram‐scale preparation was successfully performed in the presence of CuOAc catalyst under open‐flask conditions.