Organo‐phosphorus compounds. I. Interaction of organic phosphorohalogenides with solid alkalis: A new synthesis of schradan

Tetramethylphosphorodiamidic chloride reacts with alkali‐metal hydroxides via the alkali salt to give the anhydride (bisdimethylaminophosphonous anhydride, octamethylpyrophosphoramide, schradan) in high yield. The less stable bromide gives a lower yield of schradan. The fluoride does not yield schradan under these conditions, nor when treated with water in the presence of pyridine. Although diethyl phosphorochloridothionate yields the corresponding anhydride when treated with water in the presence of pyridine, no anhydride is formed when it is caused to react with an alkalimetal hydroxide in an inert solvent. Diethyl phosphorochloridate yields the anhydride when treated as above, but diethyl phosphorofluoridate does not. A synthesis of decamethyltriphosphoramide is described.