| Abstract: | Reactions of Subvalent Compounds of Silicon with Nitrogenheterocycles Subvalent compounds of silicon were prepared from dichloro-bis(diethylamino)silane with Na/K alloy in hexane-dimethyloxyethane containing pyridine, 4, 4′-bipyridine, indole, chinoline, lepidine, isochinoline, mono-, di- or trimethylpyridine, N-methylindole or benzofurane. Products isolated from the reaction mixtures are formed either by the insertion of a Si(NEt2)2 unit (i) into a CH bond of methyl groups to give silanes RSi(NEt2)2H (with N-methylindole, sym-collidine), (ii) into a CN bond of the heterocycle expanding the six membered ring by one unit to give silazepines, or (iii) by the addition of a ClSi(NEt2)2 unit to the nitrogen atom of the aromatic heterocycle, which results in 1, 4-dihydro(chlorosilyl)pyridine derivatives. In the silazepines lithiation and subsequent reaction with (CH3)3SiCl occurs on a CH- or CH2 group of the ring. Most compounds are characterized by elemental analyses, n.m.r. (1H, 13C and 29Si) and mass spectra; some have been identified by high resolution mass spectrometry and (or) characteristic signals in their n.m.r. spectra. X-ray structure analyses are provided for V and XX . |
