ALPHA-SUBSTITUTED PHOSPHONATES .68. ALPHA-AMINOPHOSPHONATES AND PHOSPHONO-SUBSTITUTED HETEROCYCLES FROM DIETHYL [2,2,2-TRICHLORO-1-ISOCYANATO-ETHYL]PHOSPHONATE

The easily accessible [2,?,2-trichloro-1-isocyanato-ethyl]phosphonate 1 reacts with aliphatic or aromatic amines to give the ureas 2,8. The reaction of these ureas with morpholine has been studied. Quite differ ent reaction products have been isolated or observed depending on reac tion time and the amine used for the urea formation. Oxazoles 4,10 are obtained if the ureas 2,8 were prepared from 1 and aliphatic amines o r secondary amines. Surprisingly, ureas derived from 1 and aromatic pr imary amines furnish mixtures of oxazoles 4, guanidines 5, and imidazo les 6 via ring opening-closure sequences which have not been known so far. However, the urea 2i prepared from o-hydroxyaniline gives heteroc yclic substituted alpha-aminophosphonate 7. Under acidic conditions th e oxazoles 4,10 are hydrolysed to alpha-aminophosphonates II.