4,4,6,6-Tetrachloro-2,2-(2,2-dimethyl-propane-1,3-diyldioxy)-1,3,5,2 lambda(5),4 lambda(5),6 lambda(5)-triazatriphosphorine

The title spirocyclic compound (alternative name: 2,2,4,4-tetrachloro-9,9-d imethyl-7,11-dioxa-1,3,5-triaza-2 lambda (5) 4 lambda (5),6 lambda (5)-trip hosphaspiro[5.5]undeca-1,3,5-triene), C5H10Cl4N3O2P3, does not contain alte rnating long-short P-N bond lengths in the phosphazene ring [P-N 1.559 (2)- 1.596 (2) Angstrom], as are observed in other analogous spirocyclic compoun ds. The six-membered phosphazene ring has a chair conformation in the solid state, but a conformational equilibrium in solution is indicated by NMR sp ectroscopy.