Soluble Polysilane Derivatives: Interesting New Radiation-Sensitive Polymers

Reappraisal of the Origins of the Polymodal Molecular Mass Distributions in the Formation of Poly(methylphenylsilylene) by the Wurtz Reductive-Coupling Reaction

“…Studies of the effects of a number of variables in the Wurtz reductive-coupling reaction have shown that the yields and molecular weight distributions of the product polymers can be greatly influenced by solvent effects, [20][21][22] the nature of the metal, [23][24][25] the active surface of metal, 26,27 reaction temperatures, 21,28,29 the addition of phase transfer catalysts, 9,28,30 and even the rate and order of addition of the dichlorosilane. 5,21 Depending on the nature of the substituents and the specific reaction conditions, the molecular weights of the products vary from a few thousand to several million.…”

Structural studies of oligosilanes produced by catalytic dehydrogenative coupling of primary organosilanes

“…Despite the difficulty of controlling the heterogeneous Wurtz-type coupling, and the problems of by-products and of handling liquid alkali metals, these reactions are still the only source of high molecular weight polysilylenes. All of the information regarding the interesting properties of polysilanes as silicon carbide fibre precursors (5) and as photoactive materials (6) has been obtained with such materials. Recently, a report has appeared of the catalytic redistribution of di-and other oligosilanes to give higher molecular weight polysilanes (7).…”

Photoconductive Polysilanes Bearing Charge-photogenerating Groups Based on Carbazole. 1 Synthesis via the Reductive Coupling of Diorganodichlorosilanes with Sodium

“…It was observed that in the reaction of 1a with a dispersion of Na in refluxing toluene or xylene, containing eventually some diglyme (15% v/v) which often improves the overall yield of polymer (11)(12)(13), the characteristic purple color did not appear even after prolonged heating (25 h). In addition, the 1 H-NMR (nuclear magnetic resonance) spectrum of the reaction mixture, after filtration of unreacted Na and evaporation under reduced pressure of the volatile compounds, showed that 1a remained unchanged.…”