Wurtz coupling reduction with

Pillot and coworkers113 reported the Wurtz polymerization of 2,4-dichloro-2,4-disilapentane (DCDP, 3, to give a precursor to SiC (Scheme 9). DCDP was synthesized via Mg/Zn coupling of dichloromethane 1 with excess methyldichlorosilane 2 in ca 35% yield. DCDP was polymerized via Wurtz coupling, followed by I.iAIILt reduction of residual Si—Cl, to poly(disilapentane), 4, in 61% yield with M = 1400 Da and PDI = 3.1. No polymer yields were given for 4. 

Polysilylenes are usually prepared by the Wurtz-type reductive coupling of dichlorosilanes with alkali metals. 

Jones et al. prepared poly(methylphenylsilylene) (p(MPSi)) using a Wurtz-type reductive coupling reaction, followed by reaction with (4-chloromethyl-phenylethyl) dimethylchlorosilylene to produce the a,co-difunctional ATRP initiator [240]. H NMR characterization indicated the presence of several different types of chains ends however, the majority of them appeared to contain the... 

Reductive coupling of trimethylsUyl chloride and 1,4-disilylation of benzene. (MejSi)2 is formed in 89.9% yield by the Wurtz coupling. Using 4,4 -di-/-butyl-biphenyl as an electron-transfer agent, the sonochemical reaction with benzene gives 3,6-bistrimethylsilyl-l,4-cyclohexadiene almost quantitatively. 

The synthesis of polysilanes by the Wurtz-type reductive-coupling reaction is shown in Scheme 11.6. It is applicable to the synthesis of any polysilane, the substituents of which can withstand the harsh reaction conditions. This limits the systems to ones with aUcyl, aryl, silyl, fluoroalkyl, and ferrocenyl substituents but other structures are accessible through post-polymerization chemistry. ... 

Intramolecular Wurtz couplings of 1,3-dihalogenocyclobutanes have been reported as convenient approaches to bicyclobutanes. Lithium reduction of 2,2,4,4-tetra-methylcyclobutane-l,3-dione shows an e.s.r. spectrum consistent with the anion radical (522), presumably formed via cleavage of the bicyclobutane (521). ... 

Compared to the Wurtz method, electrochemical reduction with alkaline-earth metals is a milder alternative coupling reaction with the corresponding organochlorosilane. The silanes that can react with Mg are not preferred for this approach. Regardless of this limitation, the electrochemical method is applicable to phenyl-containing chlorosilane because Mg and Mg-Cu are not reactive when in contact with water and air. The water- and/or air-sensitive reactions are not welcome for technical reasons. 

Furthermore, the commonly observed side reactions, such as reduction and enolization, were minimal. The reaction also proceeded cleanly with allylic, vinylic and even benzylic halides, where Wurtz coupling normally predominates. 

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