CHEMISTRY OF THE 4,5-BENZO-3-METHYL-1,3,2 -OXAZAPHOSPHORINAN-6-ONE RING-SYSTEM - X-RAY CRYSTAL-STRUCTURE ANALYSIS OF A BIS(2-CHLOROETHYL) AMINO-SUBSTITUTED AND OF AN ACETAMIDO-SUBSTITUTED DERIVATIVE

The reaction of zo-2-chloro-3-methyl-1,3,2-oxazaphosphorinan-6-one 1 w ith 1,2-bis-(trimethylsiloxy)ethane led to the bisphosphoryl species 2 a and to the isomeric bisphosphite derivative 2b. The reaction of 1 wi th heptamethyldisilazane furnished the expected diphosphorus compound 3, with two lambda(3)P(III) atoms linked by a methylamino group. Subst itution of the chlorine atom of 1 by the 2-chloroethylamino and bis(2- chloroethyl)amino group led to the oxazaphosphorinanones 4 and 6. By o xidation of 4 with the hydrogen peroxide/urea l:l-adduct, the phosphor yl compound 5 was formed. Oxidation of ethyl-amino-3-methyl-1,3,2-oxaz aphosphorinan-6-one 7 [1] with hydrogen peroxide, sulfur and selenium led to the corresponding phosphoryl, thiophosphoryl and selenophosphor yl compounds 8-10. Analogously, the reaction of the dimethylamino- and acetamido-substituted derivatives 11 and 13 [1] with elemental sulfur furnished the thiophosphoryl compounds 12 and 14. X-ray crystal struc ture determinations of 4 and 14 confirmed the molecular structures, pr oposed in accord with NMR spectroscopic and mass spectrometric data. T he heterocyclic rings are essentially planar. In 14 a hydrogen bond N- H...O (amide) is observed.