ABSTRACT

Substituted 2-phenylbenzo[d]thiazoles were synthesized by stirring a mixture of aldehyde and 2-aminothiol in CH2Cl2 at room temperature using Phenyltrimethylammonium tribromide as a catalyst. We show here that Phenyltrimethylammonium tribromide, a stable, crystalline organic ammonium tribromide, can be readily utilized as an alternative electrophilic bromine source. It is easier to control the stoichiometry of addition with an organic ammonium tribromide, which minimizes aromatic bromination caused by excess reagent. It brings about the efficient oxidative cyclization of benzaldehydes and 2- aminothiols to the corresponding benzothiazoles under mild conditions via condensation.