Organo-silicon compounds

Substantial research has also been performed on organo compounds of the metalloids. Silicon compounds particularly have played a major role, as witness the monograph by Voronkov 270) and the articles by Fessenden and Fessenden 86) and Garson and Kirchner 107). Silicones, because of their inertness to biological processes, have been used as heart valves, blood vessels, implants, ointments, etc. 192). Other organosilicon compounds are extremely active biologically 270a). 

Organo-compounds of the group 14 elements include some important commercial products, and we have already discussed silicones in Section 13.10 and Box 13.12. Organotin compounds are employed as polyvinylchloride (PVC) stabilizers (against degradation by light and heat), antifouling paints on ships, wood preservatives and... 

Silicon.73 The organo compounds of Si and Ge are very similar in their properties, although Ge compounds74 have been less extensively studied. We discuss only Si compounds. 

Andrianov, K.A. Organo-silicon Compounds Goskhi-mizdat Moscow, 1955 (in Russ.). Andrianov, K.A. Organo-silicon Polymer Compounds Gosenergoizdat Moscow, 1946 (in Russ.). 

Organo-compounds of the group 14 elements include some important commercial products, including poly-siloxanes silicones) discussed in Section 14.10 and... 

The thermal stability of silicon mbber compounds was evaluated with thermogravimetric analysis (TGA). The decomposition temperatures of unfilled silicon mbber, silicon mbber/organo-MMT nanocomposite, and silicon mbber/ aerosilica filled compound were 381"C, 433"C, and 440"C, respectively, as shown in Fig. 12.5. This advantageous elevation in the decomposition temperatures of silicon mbber with organo-MMT or aerosiUea ineorporation ean be attributed to the favorable interaction between the silieon mbber matrix and filler particles, which increases the physical and chemical crosslinks which prevents the silicon chains from the degradation. It is also likely that these... 

Silicone fluids containing Si—H groups are also used for paper treatment. The paper is immersed in a solution or dilute emulsion of the polymer containing either a zinc salt or organo-tin compound. The paper is then air-dried and heated for two minutes at 80°C to cure the resin. The treated paper has a measure of water repellency and in addition some anti-adhesive properties. 

Two-part room temperature condensation cure. Silicone can be formulated into two-part systems [3,12,14,33] that prevent the reactive groups from coming into contact before they are needed. The reactions in these systems are based on the condensation of a silanol group with an alkoxy silane group, catalyzed by organo-tin compounds (Scheme 9). 

C. Eabom and R. W. Bott, Synthesis and reactions of the silicon-carbon bond, Organo-metallic Compounds of the Croup IV Elements, ed. A. G. MacDiarmid, Vol. 1, Part 1. Marcel Dekker, New York (1968). 

These TMS-carbamate-mediated NCA polymerizations resemble to some extent the group-transfer polymerization (GTP) of acrylic monomers initiated by organo-silicon compounds [40]. Unlike GTPs that typically require Lewis acid activators or nucelophilic catalysts to facilitate the polymerization [41], TMS-carbamate-mediated NCA polymerizations do not appear to require any additional catalysts or activators. However, it is still unclear whether the TMS transfer proceeds through an anionic process as in GTP [41] or through a concerted process as illustrated in Scheme 14. 

Tacke, R., and Wannagat, U. Syntheses and Properties of Bioactive Organo-Silicon Compounds. 84,1-75(1979). 

Today two directions of research are of interest On the one hand, investigations on the reactivity of basic systems are important to elucidate the typical" Si=E-multiple bond properties, in particular with respect to their use as synthons in organo silicon chemistry without being hampered in their synthetical potential by bulky substituents in this context, a comparison on their reactivity with the carbon analogues is still attractive. On the other hand, the isolation of new stable unsaturated silicon compounds and their structure determination continues to be of interest for quite a number of research groups worldwide. 

Silicon compounds substituted by 2-(dimethylaminomethyl)phenyl groups [C6H4CH2N(CH3)2]nSiX4 n (X = Cl, H, organo group, n = 1 - 4) are available by the reaction of the appropriate chlorosilanes with 2-(dimethylaminomethyl)phenyllithium [4],... 

Transition-metal chemistry is currently one of the most rapidly developing research areas. The record of investigation for compounds with metal silicon bonds is closely comparable to that for silicones it was in 1941 when Hein discovered the first metal silicon complex, followed by Wilkinson in 1956. A milestone in the development of this chemistry was Speier s discovery of the catalytic activity of nobel metal complexes in hydrosilylation reactions in 1977. Hydrosilylation is widely used in modem organic syntheses as well as in the preparation of organo functionalized silicones. Detailed investigations of the reaction mechanisms of various catalysts continue to be subject of intense research efforts. 

The single-bond compounds between Si, Ge, and Sn and chalcogens (S, Se, Te) are reactive and used as synthetic intermediates in the synthesis of organic compounds, organochalcogen compounds, organo-silicon, -germanium and -tin compounds, and transition metal-chalcogen complexes and clusters. 

The reaction described is of considerable general utility for the preparation of benzoyloxy derivatives of unsaturated hydrocarbons.2"8 Reactions of 2-butyl perbenzoate with various other classes of compounds in the presence of catalytic amounts of copper ions produce benzoyloxy derivatives. Thus this reaction can also be used to effect one-step oxidation of saturated hydrocarbons,9, 10 esters,6,11 dialkyl and aryl alkyl ethers,12 14 benzylic ethers,11,15 cyclic ethers,13,16 straight-chain and benzylic sulfides,12, 17-19 cyclic sulfides,11,19 amides,11 and certain organo-silicon compounds.20... 

D. Avnir, L. C. Klein, D. Levy, U. Schubert and A. B. Wojcik, Organo-silica sol-gel materials, in Organic Silicon Compounds, ed. Z. Rappoport and Y. Apeloig, John Wiley Sons, 1998, vol. 2. 

Transformations of (Organo)silicon Compounds Catalyzed by Indium Complexes... 

Although, among the catalyhc conversions of (organo)silicon compounds, hydro-silylation remains the most commercially used process, a variety of other reactions catalyzed by transihon-metal complexes have been idenhfied and developed during the past two decades. 

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