Polymers Wurtz coupling, dichlorosilanes

Scheme 2. Wurtz Coupling of Enantiopure Dichlorosilanes and the Structure of the Resulting Chiral Polymers...

The most common route to polysilane-high polymers is by the Wurtz-type alkali metal-mediated polycondensation of dichlorosilanes. However, , u-dihalooligosi lanes can also be coupled in a similar manner. Wurtz-type polymerization of BrSiMe2SiR2SiMe2Br led to bimodal molecular weight distributions of alternating co-polymers of the type (SiMe2SiR2SiMe2) (R = hexyl or Bu),17 as in Equation (1). 

All of the polysilanes used in this study were prepared by the modified Wurtz-type coupling of substituted dichlorosilanes by sodium dispersion in an inert aromatic solvent as previously described (23.24). Poly(di-n-hexylgermane) was similarly prepared from di-n-hexyldichlorogcrmane (16). All of the polymer samples... 

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