Silicon compounds acylsilanes

Substituted aroyl- and heteroaroyltrimethylsilanes (acylsilanes) are prepared by the coupling of an aroyl chloride with (Me3Si)2 without decarbonylation, and this chemistry is treated in Section 1.2[629], Under certain conditions, aroyl chlorides react with disilanes after decarbonylation. Thus the reaction of aroyl chlorides with disilane via decarbonylation is a good preparative method for aromatic silicon compounds. As an interesting application, trimel-litic anhydride chloride (764) reacts with dichlorotetramethyidisilane to afford 4-chlorodimethylsilylphthalic anhydride (765), which is converted into 766 and used for polymerization[630]. When the reaction is carried out in a non-polar solvent, biphthalic anhydride (767) is formed[631]. Benzylchlorodimethylsilane (768) is obtained by the coupling of benzyl chloride with dichlorotetramethyl-disilane[632,633]. 

The data, which are relatively self-consistent regardless of the method, indicate that acylsilanes and acylgermanes are significantly more basic than their carbon analogs for both trimethyl and triphenyl derivatives. In each case, the silicon compound is slightly more basic than the germanium compound. 

Acylsilanes are a class of compounds in which a silyl group is directly bound to the carbonyl carbon, and they have received considerable research interest from the point of view of both physical organic and synthetic organic chemistry [15]. Acylsilanes have a structure quite similar to the structure of a-silyl-substituted ethers a silyl group is attached to the carbon adjacent to the oxygen atom, although the nature of the C-O bond is different. Therefore, one can expect /1-silicon effects in the electron-transfer reactions of acylsilanes. 

The structural chemistry of silicon bonded to special functional groups such as acetyl group, cyanide and isocyanide deserves special attention. Acylsilanes having the general formula l SiC.OR constitute an interesting class of chemical compounds. They are sensitive to light and rather unstable, particularly in a basic environment, where they react... 

Silenolates 26, i.e. silicon analogues of enolates, are formed, as shown by Ishikawa and coworkers, when sterically congested tris(trimethylsilyl)acylsilanes 25 are treated with silyllithium compounds (Scheme 10)87a b c The silyllithium reagent does not add to the C=0 bond but exclusively cleaves a Si—Si bond, yielding the corresponding silenolate 26. 

In this chapter silylmethylamines are defined as compounds in which one silicon and one nitrogen atom are directly linked to an sp3-carbon atom. This excludes, for example, enamines1 or imines2 of acylsilanes, a-silylpyridine3 and a-silylpyrroles4 derivatives (in which central carbon is sp2 hybridized) and silyldiazomethanes.5 In the literature, primary amines of this type are commonly referred to as aminomethylsilanes, silylmethylamines, 1-silylamines, a-silylamines, or 3-sila-l-aza-propanes derivatives. In this chapter,... 

Four-membered rings containing three silicon atoms (compounds of type 2) were prepared by reaction of acylsilane with Et3GeLi in THF <1999JA8118> or by thermal rearrangement of trans-silane 32 <2006AGE6371>. 

Acylsilanes, compounds in which a carbonyl group is directly attached to a silicon atom, have been much investigated using photochemical methods. The chemistry of acylsilanes has been reviewed94 and an excellent review and discussion of all the details of acylsilane photolysis has recently been published1. 

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