Organochlorosilanes metal

A second synthetic procedure for preparing silylated arene complexes, based on the metalation of a preformed rj6-arene complex, followed by treatment with an organochlorosilane, has been used only in one case so far namely, bis(benzene)chromium (47) ... 

Similarly to triacetoxymethylsilane, acetylation of chlorosilanes with metal acetates can also yield tetraacetoxysilane and other al-kyl(aryl)acetoxysilanes. The physicochemical properties of important acy-loxyorganosilanes are given in Table 13. The practical value of acetoxysi-lanes is that their hydrolysis, unlike the hydrolysis of organochlorosilanes, forms weak acetic acid, rather than hydrogen chloride. That is why acetox-ysilanes can be used to waterproof various materials (textiles, paper, etc.). Alkyl(aryl)acetoxysilanes are also used to obtain some silicone varnishes and as hardeners for low-molecular silicone elastomers. 

Metal-fragment substituted silanols are known to be stable towards self-condensation due to the strongly reduced acidity of the Si-OFI proton [2], However, these species show ready reaction with organochlorosilanes RsSiCl, which gives access to metallo-siloxanes [2], constituting attractive models for transition metal complexes anchored on silica surfaces. 

Silylene intermediates are also implicated in the reactions of certain organochlorosilanes with alkali metal vapors. Thus, treatment of (75) with K/Na alloy vapors afforded the b (C-H) insertion products (76) in a yield less than 10 of the corresponding alkenylsilane, the ) (C-H) insertion product (Equation (13)) <85JOM(292)i89>. 

However, the facile isolation of metallo-silanols allows controlled condensation reactions with organochlorosilanes in the presence of an auxiliary base leading to transition metal substituted oligosiloxanes which can be considered as model compounds for silica-immobilized catalytic systems (Eq. 2a). 

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. 

Metallaspirofluorenes 81 and 9,9-dichloro-9-silafluorene (82) were prepared by high temperature reactions of 2,2 -dihalogenobiphenyl with Ge or Sn powder or organo-chlorosilanes. The dichloride 82 was obtained in high yield by thermal reaction of (o-chlorophenyl)phenyldichlorosilane with various organochlorosilanes . Substitution reactions on the metal also led to other functional metallafluorenes. ... 

Metallation of norbornadienes by Li or Na followed by interaction with chloroalkylsilanes [181] as well as interaction of Cl (or Br) Mg-methylnor-bornene with organochlorosilanes also resulted in norbornenes bearing silicon-containing groups [182]. 

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