Reaction of isocyanates derived from chloromethylphosphonic and -phosphinic acids with acetic acid. Synthesis of 1,4,2-diazaphospholidines

Addition of acetic acid to bis(chloromethyl)phosphinoyl isocyanate yields N -[bis(chloromethyl)phosphinoyl]urea, tetra(chloromethyl)pyrophosphinate, an d acetic anhydride. A similar reaction with phenyl (chloromethyl)isocyanato phosphonate proceeds much slower and leads to formation of structurally sim ilar products. The phosphorylated ureas were also prepared by addition of a mmonia to the same phosphorylated isocyanates, Under the action of bases th e phosphorylated ureas cyclize to 1,4,2-diazaphospholidines. A theoretical study of the cyclization pathways of the phosphorylated ureas was performed by the MNDO method using the MOPAC 6.0 program.