Silanes involved in dehydrocoupling

Selected Examples of Dehydrocoupling of PhSiH3 by Metallocenes of Group 4 

In his first publication4 reporting the use of Cp2TiMe2 to polymerize primary silanes, Harrod also described the condensation of PhMeSiH2 in toluene and the coupling of this secondary silane occurred much more 

Therefore, reduction of steric hindrance allows the formation of oligomers higher than the disilane. 

As a last comment, an attempt to dehydrocouple the labeled secondary silane, PhMeSiD2, to give D(PhSiMe)xD, with Cp2ZrCl2/2 BuLi demonstrated another process that was promoted by this catalyst system.50 Analysis of the oligomer mixture produced revealed that although each oligomer had approximately two deuterium atoms (determined by mass spectroscopy), the label had scrambled between the SiH and CH (methyl group) positions as determined by H and 2H NMR spectroscopy. 

There are several reports of the condensation of bis-silanes of the type H3Si-X-SiH3 (primary silanes) and H2RSi-X-SiR H2 (secondary silanes) principally with the aim of producing polymers that would be precursors to silicon carbide ceramic material. The polymers would, in principle, 

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