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-, C-13-, P-31-NMR, HETCOR, and MS. The structure of the spiro-cyclic phosphazene (9) has been examined crystallographically. It crystallizes in the P2(1)/n space group with a= 10.7906(10) angstrom, b=8.5625(17) angstrom, c=21.187(5) angstrom, beta=91.298(12)degrees, V= 1957.1(6) angstrom(3), Z=4 and D-x= 1.660g 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. (c) 2005 Elsevier B.V. All rights reserved.