Wurtz-type couphng

Polysilanes (or polysilylenes) are usually prepared by the Wurtz-type couphng reaction of dichlorodialkylsilanes or, alternatively, via a transition metal-catalyzed dehydrogenation of dialkylsilanes both approaches often exhibit difficulties in terms of controlling the molecular weight and chain-structure, however. Nonetheless, by using masked silylene monomers (l-phenyl-7,8-disilabicyclo[2.2.2]octa-2,5-dienes), a series of novel, well-defined linear poly(silylene)s (M /Mn 1.3) was successfully obtained via an anionic ROP (Scheme 5.11) [147-150]. 

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