CHEMISTRY OF THE 1,3,5-TRIAZA-2-PHOSPHORI NAN-4,6-DIONES .9. REACTIONOF SOME O-1,3,5-TRIAZA-2-LAMBDA(3)-PHOSPHORINAN-4,6-DIONES WITH HEXAFLUOROACETONE

The reactions of roethyl)amino-1,5-dimethyl-3-phenyl-1,3,5-triaza-2 la mbda(3)-phosphorinan-4,6-dione (1), 2-bis(2-chloroethyl) amino-1,5-dim ethyl-3-phenyl-1,3,5-triaza-2 lambda(3)-phosphorinan-4,6-dione (2), 2- methoxy-1,3,5-trimethyl-1,3,5-triaza-2 lambda(3)-phosphorinan-4,6-dion e (3) and 2-trimethylsiloxy-1,3,5-trimethyl-1,3,5-triaza-2 lambda(3)-p hosphorinan-4,6-dione (5) with hexafluoracetone are described. In the case of 2 and 3 the reaction furnished the spirocyclic compounds 7 and 8. (2-chloroethyl)amino-1,3,5-triphenyl-1,2,5-triza-2 lambda(3)-phosp horinan-4,6-dione (4) did not react. In the case of 1 and 5 rearrangem ent reactions took place; the (2-chloroethyl)amino substituent of 1 re acted with one of two equivalents of hexafluoroacetone with formation of the spirocyclic phosphorane 6. The reaction of 5 with tetrabromoort hobenzoquinone gave the phosphoryl compound 9. Compounds 6-8 were char acterized via their H-1-, C-13-, F-19- and P-31-NMR and mass spectra, compound 9 via its H-1-, C-13- and P-31-NMR and mass spectra. An X-ray crystal structure determination of 8 was conducted; in the six-member ed ring the phosphorus atom lies 73 pm out of the plane of the other a toms, and displays trigonal bipyramidal coordination.