NEW PHOSPHOLENE AND PHOSPHEPINE DERIVATIV ES FROM LAMBDA(3)-PHOSPHORUS COMPOUNDS AND HEXAFLUOROACETONE OR PERFLUORINATED ALPHA-DIKETONES

The reaction of the bis (2-chloroethyl)amino-substituted benzoxazaphos phorinone 1 with hexafluoroacetone (HFA) proceeds with insertion of th e carbonyl group of HFA into the heterocycle of 1 to form the oxazapho sphepinedione 2. Triethyl phosphite (3) and triphenyl phosphite (4) re act with the perfluorinated diketones 5 and 6 with formation of the pe ntaoxyphosphoranes 7-10 containing a dioxaphospholene ring system. The reaction of the (2-chloroethyl)amino- and bis(2-chloroethyl)amino-sub stituted 1,3,5,2-triazaphosphorinanediones 11-14 with the perfluorinat ed diketone C2F5C(:O)C(:O)CF3 (15) furnishes spirophosphorane derivati ves with the dioxaphospholene ring system, 16 and 17, in two cases onl y. Compound 1 and 2-[bis (2-chloroethyl) amino]-4H-1,3,2-benzodioxapho sphorin-4-one (18) react with the perfluorinated alpha-diketones 5 and 6 with insertion of the diketones into the heterocycle of 1 and 18 wi th formation of compounds 19-22 containing dioxa- and oxazaphosphepino ne ring systems. The expected oxidative addition of the diketones to l ambda(3)P with formation of spirophosphoranes was not observed. Compou nds 19-22 were obtained as mixtures of isomers (19a/b-22a/b). Single c rystal X-ray structure analyses were conducted on 2 and 9. The seven-m embered ring of 2 displays a ''tub'' conformation, with the O and benz o C atoms lying out of the plane of the other four atoms. The two inde pendent molecules of 9 are similar, but differ in the degree of distor tion from trigonal-bipyramidal geometry of phosphorus.