New cyclic and spirocyclic aminosilanes

New cyclic and spirocyclic aminosilanes were synthesised using ethylenediamine, 2-aminobenzylamine, 1,8-diaminonaphthalene, o-phenylenediamine, and trans-cyclohexane-1,2-diamine as starting material. These diamines were converted into aminosilanes using silicon tetrachloride and dimethyldichlorosilane directly and via the N,N’-bis(trimethylsilylated) amino derivatives. 15 new compounds of the type (diamino)(SiMe3)2, (diamino)2Si, (diamino)SiMe2, and (diamino)SiCl2 have been prepared. The formation of two cyclotrisilazane derivatives was observed starting from (N,N’-2-aminobenzylamino)dichlorosilane by trimerisation. All synthesised compounds have been characterised with NMR-, Raman-, or IR-spectroscopy, mass-spectrometry, and boiling or melting point. Single-crystal X-ray structure analyses of several derivatives have been performed.