2-Chloroethyl isocyanate → alpha-[N-(2-chloroethyl)ureido]benzylphosphonic acid diethyl ester

Participants

Reaction Conditions

Reaction Steps

A solution of 0.05 mol of α-aminobenzylphosphonic acid diethyl ester in 30 ml of chloroform is cooled to 0° C. in an ice-bath and then a large excess (0.06 mol) of β-chloroethyl isocyanate is added. The temperature of the reaction is then maintained at 10° C. while continuing stirring until the reaction is complete. (Examination by thin layer chromatography is used to ascertain that the starting aminophosphonate has disappeared completely. After evaporation of the solvent under reduced pressure, the crystalline residue is taken up in ether and filtered, yielding 14.8 g of crystals. Yield: 85%; m.p.=82° C.

Provenance & Evidence