The vinyloxycyclophosphazene derivatives, N3P3Cl5OCHCH2 (1) and N4P4Cl7OCHCH2 (6), undergo radical polymerization to produce the highly functionalized homopolymers [CH(ON3P3Cl5)CH2] n (7) and [CH(ON4P4Cl7)CH2] n (8). These materials undergo a remarkable two-step thermal decomposition process. The first step is an exothermic cross-linking reaction involving the elimination of HCl at modest temperatures. The activation energy for the first step is lower for 7 than for 8. The second step is an endothermic elimination of the oxo-bridged cyclophosphazene dimer, (N3P3Cl5)2O. Copolymers have been obtained from mixtures of 1 and 6. The calculated reactivity ratios show a preference for incorporation of 1 over 6 into the copolymers. Attempted copolymerization of 1 with styrene leads to mixtures of the respective homopolymers. Attempts to polymerize N3P3X5OCHCH2 [(X = F(2), OCH3 (3), OCH2CF3 (4), N(CH3)2 (5)] lead to various outcomes including insoluble materials, oligomers, or recovery of unreacted monomer. The sensitivity of the polymerization to the nature of the phosphazene substituents has been related to monomer electronic structure and reactivity of the exocyclic groups.

The reactions of the lithium enolate of acetaldehyde, LiOCHCH2, with hexachlorocyclotriphosphazene, N3P3C16, lead to the series of (vinyloxy)chlorocyclotriphosphazenes, N3P3Cl6_"(OCH=CH2)" (n = 1-6). Evidence for the occurrence of all possible geometrical and positional isomers in the series has been obtained from the 31P NMR spectra. The principal products are the nongeminal species with comparable amounts of cis and trans isomers being formed. Small amounts of the geminal isomers are also observed. The mono-and pentasubstituted derivatives have been converted to their dimethylamino derivatives, N3P3(OCH=CH2)6."[N(CH3)2]" (n = 1, 5).

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The reactions of LiC-CSiMe, with N3P3F6 lead to the new alkynylphosphazenes N3P3F6-n(C-CSiMe3)n (n = 1 or 2). Both the geminal and non-geminal isomers are observed in the 3IP and '9F n.m.r. spectra. A reinvestigation of the reaction of LiC-CC6H5 with N3P3F6 showed that, at the stage of bis substitution, in addition to the previously reported major product, gem-N3P3F4( CrCC6H5)2, small amounts of the non-geminal N3P3F4(CfCC6H5)2 isomers are formed. The reactions of N3P3F6-,( C-CSiMe3), (n = 1 or 2) with KF in anhydrous ethanol lead to the terminal acetylene derivatives, N3P3F4-,(OC2H5)2(CZH)n (n = 1 or 2).The reactions of organolithium and Grignard reagents with halogenophosphazenes have been shown to be valuable routes to organophosphazenes.2 Much of the effort in this area has been devoted to a r ~l -~-~ and a l k ~l -~* ~* substituted species with alkenyl 1*2*6-8 and especially alkynyl 2*9*10 derivatives being less common. We are particularly interested in alkenyl-and alkynyl-phosphazenes because of the potential, as shown in our work on propenylphosphazenes, for further synthetic transformations into organophosphazene polymers 2*11*12 and new organopho~phazenes.~~~*~~ A previous study by Chivers involving phosphazene derivatives of phenylacetylene, N3P3F6-,(CXC6H5), (n = 1 or 2), demonstrated the viability of synthesis of alkynylphosphazenes. Alkynylphosphazenes have also been observed in the reactions of copper or lithiophosphazene anions with prop-2-ynyl bromide leading to materials of the type N3P3C14R(CH2C-CH) (R = alkyl or allyl).'O Rearrangement from the prop-2ynyl to the prop-I-ynyl derivative, N3P3C14R(C-CCH3), was also observed.'O A prop-I-ynyl derivative, N3P3F5(CfCCH3), was previously reported as a by-product in the reaction of the 1 it hiopropene LiCH=CHCH3 with N3P3F6 .7In this paper we describe the synthesis of phosphazenes with trimethylsil ylacet ylene and terminal acetylene subs t i t uen t s. ExperimentalMaterials and Methods.-Hexafluorocyclotriphosphazene, N3P3F6, was prepared from N3P3C16 (Ethyl Corp.) by a previously reported pro~edure.'~ Phenylacetylene and n-butyllithium (1 3 5 mol dm-3 solution in hexane) were obtained from Aldrich Corp. Trimethylsilylacetylene was obtained from Petrarch systems. Diethyl ether and tetrahydrofuran were distilled from sodium benzophenone ketyl. Light petroleum (b.p. 35-55 "C) was distilled over sodium.N.m.r. spectra (in CHCI,) were recorded on a Bruker WM250 spectrometer operating at 250.1 ('H), 62.9 (13C), 235.2 (19F), or 101.2 MHz ("P). For 31P n.m.r., 85% H J P O ~ was used as external reference, for 19F, CFCl, was used. The I3C, I9F, and ,lP n.m.r. spectra were recorded under conditions of broad-band decoupling. Due to the complex second-order nature of the 19F and 31P spectra, parameters reported for these systems are approximate. Chemical shifts upfield of the reference are assigned a negative sign. Infrared (i.r.) spectra were obtained from thin films (NaCl discs) on a Beckman IR 20A spectrometer. Mass spectra were recorded on a Perkin-Elmer RMU-6D...

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