| Abstract: | Stabilization of ? P?C〈 Bonds by Cyclic Silylhydrazones 1,2-Diaza-3-sila-5-cyclopentenes unsubstituted at the 4-position react after lithiation with halophosphanes and -arsanes to give 1 – 4 . The 4-methylated ring 5 reacts analogously with F2P? N(SiMe3)2 to give 6 , but exchanges the dimethylsilyl group of the ring in reaction with PCl3, to give 1,2-diaza-3-phospha-3,5-cyclopentadien 7 . The phosphaethenes 8 and 9 are formed from 4-trimethylsilylsubstituted lithiated rings by reaction with difluorophosphanes, F2PR (R = N(SiMe3) CMe3, N(SiMe3)2) and elimination of LiF and chlorosilane. |
