Tetramethylphosphorodiamidic chloride

With some compounds, e.g. tetramethylphosphorodiamidic chloride, POCl(NMe2)2, certain other salts were also effective fluorinating agents. 

A synthetic approach to /3-sultams containing a direct bond between a tri- or tetracoordinated phosphorus atom and the nitrogen atom of the 1,2-thiazetidine 1,1-dioxide ring has been realized by direct phosphitylation or phosphorylation at nitrogen. Unfortunately, attempts to synthesize N-phosphorylated /3-sultams by reaction with diethyl phosphorochloridate and diethyl phosphorobromidate, generated in situ from diethyl phosphate and carbon tetrachloride or carbon tetrabromide, failed. However, when the /3-sultam is treated with freshly distilled diethyl phosphorochloridite or tetramethylphosphorodiamidous chloride in the presence of triethylamine, the expected AHliethy I phosphite and iV-phosphorodiamidous /3-sultams 150 are obtained (Equation 10). /3-Sultams unsubstituted... 

A solution of 100 g (0.61 mole) of trimethyl(phenylmethyl)silane [Pfalz and Bauer] and 87.5 mL (0.61 mole) of AI,yV,yV, (V -tetramethyl-l,2-ethanediamine (TMEDA) [Aldrich] dissolved in 150 mL of diethyl ether is placed in a 1-L three-necked flask provided with a dropping funnel, a mercury relief valve, and a magnetic stirrer. This solution is cooled to — 20°, and 364.3 mL (0.61 mole) of a. f> M solution of butyllithium in hexane is added over a 90-min period. After being warmed to room temperature, the reaction mixture is stirred for at least 6.5 hr while the orange-yellow lithium complex salt precipitates. The mixture is cooled to -20°, and a solution of 92.7 g (0.61 mole) of N,N,N, N -tetramethylphosphorodiamidous chloride [Alfa Products] in 80 mL of diethyl ether is added over a period of 90 min. This mixture is allowed to warm to ambient temperature and is stirred for 1 hr. Then the LiCl is Altered and washed... 

Treatment of A, A, A, A -tetramethylphosphorodiamidic chloride with hydrogen sulfide gives a mixed anhydride (26) indicating that the intermediary phosphorothioate is phosphorylated at the hard oxygen. 

Fig. 14. Inhibition of horse-serum cholinesterase by various compounds. Incubated for 15 min. at 20° before addition of 2 mg. of acetylcholine chloride. A, di-isopropyl phosphorofluoridate B, di ec.-butyl phosphorofluoridate C, eserine D, diphenyl phosphorofluoridate E, dithioethyl phosphorofluoridate F, tetramethylphosphorodiamidic fluoride O, diethyl ALmethylphosphor-amidate.

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