Organophosphazenes. 17. The Synthesis of Trimethylsilylacetylene and Terminal Acetylene Derivatives of Hexfluorocyclotriphosphazene.

The reactions of lithio trimethylsilylacetylene, LiCCSiMe3, with hexafluorocyclotriphosphazene, N3P3F6, lead to the new alkynphosphazenes N3P3F6, lead to the new alkynphosphazenes N3P3F6-nCSCiMe3n n1,2. Both the geminal and non-geminal isomers are observed in the 31P and 19F n.m.r. spectra. A reinvestigation of the reaction of lithio phenylacetylene, LiCCPh, with N3P3F6 showed that, at the stage of bis substitution, in addition to the previously reported major product, gem-N3P3F4CC Ph2, small amounts of the non-geminal N3P3F4CCPh2 isomers are formed. The reactions of N3P3F6-nCCSiMe3n n1,2 with potassium fluoride in anhydrous ethanol leads to the terminal acetylene derivatives, N3P3F4-n OC2H52CCHn n1,2.