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The article provides a comprehensive account of the research on synthetic and catalytic aspects of hydrosilylation. Reactions proceeding in the presence of nucleophilic‐electrophilic catalysts, metals and immobilized metals as well as radical initiators are described. However, particular attention is paid to processes catalysed by transition metal complexes. For these catalytic systems, mechanistic pathways and development of efficient and selective catalytic systems are more comprehensively discussed. Possible applications of hydrosilylation of multiple carbon‐carbon and carbon‐heteroatom bonds in organic and asymmetric synthesis are presented. The article summarizes applications of the hydrosilylation processes in polymer and material chemistry including their contribution in polysiloxane curing, synthesis of new hybrid materials, dendrimers and functionalized molecular and macromolecular organosilicon derivatives.

. These, upon reaction with dimethylcarbonate, are selectively converted into the methyl carbamate esters MeO(O) CNH(CH 2 ) Si(OMe) , MeO(O)CNH(CH 2 ) Si (OEt) and MeO(O)CNH(CH 2 ) 2 NH(CH 2 ) Si (OMe) respectively. Carbamate MeO(O)CNH (CH 2 ) Si(OEt) is accompanied by MeO(O)CNH (CH 2 ) Si(OMe) x (OEt)3 À x formed via transesterification of the triethoxysilyl group by the co-produced methanol. The carbamation process is very selective and N-methylated species are formed in trace amounts. Conversely, the ureidofunctional silane H 2 NC(O)NH (CH 2 ) 2 NH(CH 2 ) 3 Si(OMe) 3 shows a poor reactivity towards carbamation, and, under the above conditions, N-methyl derivatives are preferably formed.

The cross-metathesis of styrene with various vinylsilanes, H 2 CdC(H)SiR 3 , catalyzed by [Cl 2 (PCy 3 ) 2 RudCHPh] (1) to give (E)-silylstyrene, (E)-Ph(H)CdC(H)SiR 3 , and ethylene is reported. The reaction proceeds even at room temperature and is highly selective. Very high conversions are observed when R ) OEt, OSiMe 3 (g95%, 6 h, 2 mol % of 1). The conversion significantly decreases with increasing substitution of Me for OR′. The metathesis is reversible. Therefore, removal of ethylene is critical for achieving high conversions. From the study of stoichiometric reactions of 1 with vinylsilanes it follows that in the series SiR 3 ) Si(OEt) 3 , SiMe(OEt) 2 , SiMe 2 OEt, SiMe 3 and SiR 3 ) Si(OSiMe 3 ) 3 , SiMe(OSiMe 3 ) 2 , SiMe 2 -(OSiMe 3 ), SiMe 3 the conversion rate increases, but simultaneously the selectivity of the metathesis decreases. The decreasing selectivity readily accounts for the decreasing efficiency in the catalytic metathesis. The product distribution of reactions of styrene-d 8 with H 2 Cd C(H)SiR 3 (R ) OEt, OSiMe 3 ) in the presence of 1 provides evidence for a metallacarbene mechanism involving [Ru]dCHPh and [Ru]dCH 2 species.

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