REACTIVE POLYSILANES .5. OPTIMIZATION OF THE SYNTHESIS OF MEGA-BIS(TRIMETHYLSILYL)OLIGO(METHYLPHENYLSILANE)S CONSIDERING AN ANIONIC MECHANISM

Low-molecular-weight organosilane polymers were prepared by sodium and potassium/sodium coupling of dichloromethylphenylsilane (1) with chlo rotrimethylsilane (2). Size exclusion chromatography (SEC), IR, UV and NMR (H-1, C-13 and Si-29) analysis of the crude omega-bis(trimethylsi lyl)oligo(methylphenylsilane) (3) were performed and compared with tho se of the isolated shortest oligomers. According to an anionic mechani sm, the solvent and alkali-metal effects on the yield and the oligomer distribution (SEC-resolved) allow an optimisation for the synthesis o f the shortest oligomers (trisilane and tetrasilane).