A process for the production of 2-aryl-2H-benzotriazoles comprises reducing and cyclizing the corresponding o-nitroazobenzenes with hydrogen at a temperature in the range of about 20.degree. C. to about 100.degree. C. and at a pressure in the range of about 15 psia (1 atmosphere) to about 1000 psia (66 atmospheres) in an alkaline medium at a pH over 10 in the presence of a nickel catalyst, preferably molybdenum-promoted Raney nickel. High yields of pure product are obtained directly with a concomitant reduction of undesired by-product and a reduction in effluent pollution problems.
生产2-芳基-2H-苯并三唑的过程包括在碱性介质中,在温度范围为约20°C至约100°C,压力范围为约15 psia(1大气压)至约1000 psia(66大气压)下,通过
氢气还原和环化相应的o-硝基
偶氮苯,并在pH大于10的条件下,在
镍催化剂的存在下进行,最好使用
钼促进的Raney
镍。直接获得高产率的纯品,同时减少不需要的副产物和减少废
水污染问题。