Reactions of 1,3,5,7-Tetrasilaadamantanes with

The use of the weaker Lewis acid AICI3 meant a reduction in reaction rate without a change in the mechanism of reaction. Although the reaction of Si-methylated 1,3,5,7-tetrasilaadamantane with AICI3 in the absence of solvent at 90 °C yielded 

An H-NMR investigation of the mass spectrometrically-identified compounds showed that an isomeric mixture of straight and branched-chain tetramers as well as n-, iso- and neo-pentane analogues of pentamers existed. The isomers of tetrameric tetrasilaadamantane could be separated and eventually isolated by HPLC. 

Between each pair of main peaks (Fig. 13) appeared three smaller signals, representing the compounds with 9, 10 and 11 13, 14 and 15 and 17, 18 and 19 Si atoms respectively. 

These correspond formally to an extension of the tetrasilaadamantane oligomers containing 1, 2 or 3 SiC3Hg structural units, as proved by a mass-spectrometric investigation of fractions Si and Si 3. 

One- to three-fold addition of SiC3Hg units to the 1,3,5,7-tetrasilaadamantane chain can be explained by consideration of two structural alternatives  

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