Ammonia—Hydrazine conversion processes: XVI. Conversion of benzophenone azine into hydrazine catalyzed by sulphonic acids in a two-phase system

Abstract

Lipophilic sulphonic acids revealed excellent activity as catalysts for the hydrolysis of benzophenone azine (Ph 2C N N CPh 2) into hydrazine in a two-phase system of xylene and 2 N sulphuric acid. High yields of hydrazine (89.8-93.2%) were obtained with a catalytic amount of dodecyl- or didecylbenzenesulphonic acid (2 mol-%, relative to the amount of azine) at 90°C for 1 h. These values are in sharp contrast to the 0.64% yield of hydrazine obtained in the absence of sulphonic acid. For high catalytic activity, dilute mineral acid should be present in the aqueous phase for effective regeneration of the free sulphonic acid. Strongly hydrophilic p-toluenesulphonic acid was extracted almost entirely into the aqueous phase and was less active catalytically at high concentrations.