Triethylamine → Phosphoramidic dichloride, bis(2-chloroethyl)-

Participants

Reaction Conditions

Reaction Steps

Bis(2-chloroethyl)amine hydrochloride (6.3 g, 35 mmol), suspended in 80 mL dichloromethane, was cooled to −78° C. under argon and stirred. A solution of phosphoryl chloride (5.41 g, 35 mmol) in 10 mL dichloromethane, followed by a solution of triethylamine (3.53 g, 70 mmol) in 10 mL dichloromethane, was added slowly by syringe. Stirring was continued while the reaction mixture was allowed to warm to room temperature overnight. The reaction mixture was washed with 0.01N hydrochloric acid (3×25 mL), dried over magnesium sulfate, and concentrated under reduced pressure to give N,N-bis(2-chloroethyl)phosphoramidic dichloride as a light orange oil that solidified on standing (7.9 g, 87% yield). A 2.2 g aliquot of the crude N,N-bis(2-chloroethyl)phosphoramidic dichloride was purified by flash chromatography on a 12 g silica cartridge, eluting with a gradient of 100% hexane to 67% hexane/33% ethyl acetate over 10 minutes followed by 67% hexane/33% ethyl acetate for a further 10 minutes, to give 1.5 g pure N,N-bis(2-chloroethyl)phosphoramidic dichloride as a white solid after evaporation of the solvents. MS (ES): m/z=275 [C4H8Cl4NOP+NH4+].

Provenance & Evidence