Ammonia → N,N-Dimethylaminophosphoryl dichloride

Participants

Reaction Conditions

Reaction Steps

Using the procedure described in M. Goehring and K. Niedenzu, Chem. Ber. 89, pp 1768-1771 (1956), 1300-1400 grams of a material containing 53.5% (by weight) of N,N-diethylphosphoric triamide and 46.5% (by weight) of ammonium chloride was prepared by reacting 1035 g of N,N-dimethylphosphoramidic dichloride and ammonia in ether at 0° C. The N,N-dimethylphosphoramidic dichloride was prepared by adding 425 g (9.45 mol) of dimethylamine to 4000 mL (6580 g, 42.7 mol) of phosphorus oxychloride at 0°-10° C., heating the reaction mixture at reflux (105° C.) for 18 h, and distilling the products at reduced pressure (31P NMR (CDCl3): δ 17.7 ppm). Pure N,N-dimethylphosphoric triamide can be obtained by extracting the crude material with chloroform, evaporating the chloroform, and recrystallizing the residue from acetone/chloroform. For example, extraction of 130 g of crude material with 1300 mL of hot chloroform provided 30 g of pure material, mp 128.5°-131° C. (lit. 119° C.), after recrystallization

Provenance & Evidence