Organophosphazenes. Part 17. The synthesis of trimethylsilylacetylene and terminal acetylene derivatives of hexafluorocyclotriphosphazene

Abstract

The reactions of LiCCSiMe₃ with N₃P₃F₆ lead to the new alkynylphosphazenes N₃P₃F_{6 –n}(CCSiMe₃)_n(n= 1 or 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 LiCCC₆H₅ with N₃P₃F₆ showed that, at the stage of bis substitution, in addition to the previously reported major product, gem-N₃P₃F₄(CCC₆H₅)₂, small amounts of the non-geminal N₃P₃F₄(CCC₆H₅)₂ isomers are formed. The reactions of N₃P₃F_{6 –n}(CCSiMe₃)_n(n= 1 or 2) with KF in anhydrous ethanol lead to the terminal acetylene derivatives, N₃P₃F_{4 –n}(OC₂H₅)₂(CCH)_n(n= 1 or 2).