Phosphorus-nitrogen compounds: New spiro-cyclic phosphazene derivatives. Structure of 4′,4′,6′,6′-tetrachloro-3,4-dihydro-3-(3-methylpyridin-2-yl)spiro-[1,3,2-benzoxazaphosphinine-2,2′-(2λ5,4λ5,6λ5-cyclotriphosphazene)]. Part XII

The condensation reactions of {N-[(2-hydroxyphenylmethyl)amino]-methylpyridines (5-8) with trimer, N3P3Cl6, have been afforded partially substituted novel spiro-cyclic phosphazene derivatives (9-12) (Scheme 1). Compounds (9-12) have been characterized by elemental analyses, FTIR, 1H-, 13C-, 31P-NMR, HETCOR, and MS. The structure of the spiro-cyclic phosphazene (9) has been examined crystallographically. It crystallizes in the P21/n space group with a=10.7906(10) Å, b=8.5625(17) Å, c=21.187(5) Å, β=91.298(12)°, V=1957.1(6) Å3, Z=4 and Dx=1.660 g cm−3. The structure consists of a non-planar phosphazene ring with a bulky methylpyridinyl and a benzo-fused spiro-cyclic side group. The six-membered spiro-cyclic ring has a twist-boat conformation.