Synthesis of 2-arylbenzimidazoles and 2-arylbenzothiazoles in both room temperature and microwave condition catalyzed by hexamethylenetetramine–bromine complex

One-pot condensation of 2-aminothiophenol or 1,2-phenylenediamine with different aldehydes has been catalyzed by hexamethylenetetramine–bromine (HMTA-Bromine) as new, available and effective catalyst. 2-Arylbenzo-thiazoles and 2-aryl-benzimidazoles have been achieved in excellent yield and good purity.