A clean and efficient strategy for the synthesis of benzothiazepines from chalcone and ortho-aminothiophenol has been reported. Here, glycerol, a biodegradable and reusable promoting medium, has been utilized under acid, base or metal-free conditions. The significant features of the protocol include a one-pot eco-friendly approach, short reaction time, high atom economy, broad substrate scope, easy workup process and high yields.