Efficient Synthesis of 2-Arylbenzothiazole Derivatives with the Aid of a Low-Valent Titanium Reagent

A novel and facile synthesis of 2-arylbenzothiazole derivatives was accomplished in good yields via the novel reductive cyclization of bis-(2-benzalaminophenyl)disulfide promoted by the TiCl4/Sm system. The advantages of this new method are the easily accessible starting materials, short reaction time, and moderate to good yields.