To a stirred solution of trans N3P3Az2Cl4 (I) in 15 ml of benzene, cooled to 5 C, a solution of 50 mmol of MeNH2 in 20 ml of benzene is added dropwise. After warming to room temperature and allowing the reaction to proceed over a period of 18 h, the temperature of the reaction mixture is raised to 50 C for an additional 6 h. The precipitated amine hydrochloride salt is filtered off and washed with benzene. The washings are combined with the filtrate and evaporated by vacuum. The crude product is recrystallized from benzene