The direct reaction of [NPCl2] n with the difunctional reagent 2,2‘-dihydroxybiphenyl (HOC6H4C6H4OH) and K2CO3 in tetrahydrofuran gave soluble linear phosphazene high polymers instead of the expected cross-linked products. The reaction of [N3P3Cl6] with 1, 2, or 3 equiv of HOC6H4C6H4OH and K2CO3 in acetone gave the known spiro derivatives [N3P3Cl4(O2C12H8)], [N3P3Cl2(O2C12H8)2], and [N3P3(O2C12H8)3] without formation of bridging products, and the dichloro derivative reacted directly with para-substituted phenols HOC6H4R and K2CO3 in acetone to give the new compounds [N3P3(OC6H4R)2(O2C12H8)2] (R = Br, COC6H5, or OCH3), without signs of replacement of the bis(aryloxy) substituents. In an analogous manner, poly(dichlorophosphazene) [NPCl2] n reacted with HOC6H4C6H4OH and K2CO3 in THF without significant cross-linking to give, depending on the mole ratio, the soluble polymer [NP(O2C12H8)] n (M w = 450 000, T g = 160 °C) or the partially substituted polymers {[NP(O2C12H8)]0.35[NPCl2]0.65} n . The latter were subsequently reacted with the para-substituted phenols HOC6H4R and K2CO3 in THF to give the random copolymers {[NP(O2C12H8)]0.35[NP(OC6H4R)2]0.65} n [R = Br, CN, COCH3, or COC6H5). The new polymers are soluble (except the CN derivative, which was sparingly soluble) white solids, with only a few ppm of unreacted chlorine, and Mw of the order of 1 000 000 with polydispersities varying from 3 to 10. The T g values varied with R ranging from 73 °C (R = CN) to 54 °C (R = COMe).

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SYNOPSISA very convenient synthetic method is described for the known cyclic aryloxyphosphazenes [N3P3(OC6H4-R)6] (R = Br, CN, CHO, COCH3, COC6H5, and NO,). The method is based on the direct reaction of [N3P3C16] with six equivalents of the para-substituted phenols HOC6H4-R and K&03 in refluxing acetone and is characterized by very short reaction times and very simple workups, leading directly to the analytically and spectroscopically pure products in very high yields. In the cases where R = H, But, or OCH3, the reactions were much slower, but the time could be shortened by using [Bu4N]Br as the phase-transfer catalyst. Similarly, the polymers [NP(OC6H4-R),], can be conveniently obtained in ca. 70% and good analytical purity from polydichlorophosphazene [NPCl,], and the parasubstituted phenols HOC6H4-R (R = Br, CN, COCH3, COC6H5, and NO2) in the presence of K2C03 using THF as the solvent.

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