Chloride → Imino-tris(dimethylamino)phosphorane

In a 5-l reactor fitted with a stirrer, a thermometer and a dropping funnel, 1.60 kg of tetrahydrofuran were weighed, followed by the addition of 250 g (1.16 mol) of aminotris(dimethylamino)phosphonium chloride. The contents were heated to 55° C., at which 2.29 kg of a 5.6 wt. % aqueous solution of barium hydroxide, said solution containing 0.83 mol (equivalent to 1.1 gram equivalents based on the chloride) of barium hydroxide, were added dropwise over 20 minutes. After completion of the dropwise addition, the resulting mixture was stirred at the same temperature for 30 minutes and was then allowed to cool down to room temperature in about 30 minutes. Iminotris(dimethylamino)phosphorane was formed with a reaction yield of 99 mol %.