Silicon containing compounds chemistry

The importance of carbon-centred radical cyclizations in organic chemistry has been documented in the large number of papers published each year and numerous reviews and books dealing with this subject. In Chapter 7 the reader can find a collection of such processes mediated by organosilanes. The silicon-centred radical cyclizations have instead received very little attention, although there has been a growing interest in silicon-containing compounds from a synthetic point of view, due to their versatility and applicability to material science. As we shall see, this area of research is very active and some recent examples show the potentiality of silyl radical cyclization in the construction of complex molecules. 

H. Bock, Angew. Chem., 101, 1659-1682 (1989), Angew. Chem., Int. Ed. Engl. 28, 1627-1650 (1989), correlates in Fundamentals of Silicon Chemistry Molecular States of Silicon-containing Compounds PES and ESR/ENDOR measurement data with first and second order MO perturbation models. 

There arc many reactions in organic chemistry in which an Me3Si group acts like a proton—Chapter 47 will detail some more reactions of silicon-containing compounds. Just as acidic protons are removed by bases, silicon is readily removed by hard nucleophiles, particularly F" or RO-, and this can promote an elimination. An example is shown here. 

Silicon occurrence, uses and essential chemistry Exposure to silicon containing compounds Nephrotoxicity of silicon containing compounds Pesticides ... 

In Volume III of the series OrganosUicon Chemistry From Molecules To Materials the editors gave a comprehensive summary about the focus of basic research activities in the wide-spread field of organosilicon chemistry and cited the relevant literature. With respect to the title the introduction of this volume deals mainly with a summary of how to make silicon-containing compounds and... 

At the IV. Miincher Silicontage, Prof. Dr. Robert Corriu, Montpellier, was honored with the Wacker Silicon-Preis for his innovative work in all Helds of organosilicon chemistry. His contributions treat fundamental molecular questions as well as the synthesis and structure of novel Silicon containing compounds and materials. 

Our ongoing strategy to develop new fluorosilicone materials has been to combine the well known preparative chemistry of silicon containing compounds with the relatively new development of perfluorocyclobutane (PFCB) aromatic ether polymers. PFCB materials are prepared by the thermal cyclodimerization of trifluorovinyl ether (TFVE) monomers." " Recently we developed a synthetic... 

This brief review has shown that the transition metals and their compounds can play a very useful role in ceramics-directed silicon chemistry. Transition metal complexes find important applications as catalysts as well as stoichiometric reactants, and the metals themselves have found more direct application in the synthesis of silicon-containing ceramics and ceramic composites. 

By contrast, the isomerization of silyl olefins and addition of silylacetylenes =C—H bond into imines catalyzed by iridium complexes appears to serve as a suitable route for the synthesis of silylfunctionahzed organic compounds. Hence, the acquisition of experimental data on catalysis by iridium complexes in silicon chemistry may be regarded as an initial stage in the quest for catalytic processes leading to the synthesis of other p-block (e.g. B, Ge, Sn, P)-carbon bond-containing compounds. 

At the same time, advances in the field of organosilicon chemistry have also been incredibly large2. Characterization of unstable species such as divalent silylenes or compounds with silicon-containing double bonds were successfully achieved for many compounds. Advances in the field of siloxanes and other polymeric materials are also remarkable. 

Decamethylsilicocene (82) can be regarded as an electron-rich silicon(II) compound containing a hypercoordinated silicon atom. The chemistry of 82 is determined by (a) the nucleophilicity of the silicon lone-pair (cr-donor function towards electrophiles, oxidative-addition processes) and (b) the weakness of the silicon-(cyclopentadienyl)carbon jr-bond rearrangement, Si—C bond cleavage). In the following section, the chem-... 

Silicone chemistry also develops by leaps and bounds. The first silicon-and carbon-containing compound, ethyl ether of orthosilicon acid, was obtained by the French scientist Ebelmen in 1844. Subsequently, in 1963, Friedel and Crafts synthesized the first silicone compound with a Si-C bond, tetraethylsilane. At the initial stages of silicone chemistry, the researchers attention was attracted to silicon, the closest counterpart of carbon. It seemed that silicon could give rise to as large a subdiscipline as chemistry itself. Yet, it was found that silicon, unlike carbon, does not form stable molecular chains from successively bonded Si atoms, and the interest for organic silicone derivatives dropped. 

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