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

摘要

The reactions of lithio trimethylsilylacetylene, LiC=CSiMe3, with hexafluorocyclotriphosphazene, N3P3F6, lead to the new alkynphosphazenes N3P3F6, lead to the new alkynphosphazenes N3P3F6-n(C=SCiMe3)n (n=1,2). 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, LiC=CPh, with N3P3F6 showed that, at the stage of bis substitution, in addition to the previously reported major product, gem-N3P3F4(C=C Ph)2, small amounts of the non-geminal N3P3F4(C=CPh)2 isomers are formed. The reactions of N3P3F6-n(C=CSiMe3)n (n=1,2) with potassium fluoride in anhydrous ethanol leads to the terminal acetylene derivatives, N3P3F4-n (OC2H5)2(C=CH)n (n=1,2).