Ruthenium complexes silanes

C4H 2OSi, Silane, methoxytrimethyl-, 26 44 CH4N, Propane, 2-isocyant-2-methyl-ruthenium complex, 26 275 C][l,4]-dithiin-2-thione, 26 389 CHfc, 1,3-Cyclopentadiene cobalt complex, 26 191-197, 309 chromium, molybdenum, and tungsten complexes, 26 343 iron complex, 26 232-241 mercury-molybdenum-ruthenium complex, 26 333... 

A variety of 1,6-diyne substrates have been investigated for activity in the HSiR3/CO system. A ruthenium complex, Ru3(CO)12, with a tertiary phosphine additive catalyzes the formation of good yields of catechol products in which one molecule of diyne, two molecules of CO, and one or two molecules of silane are incorporated, as seen in Eq. (39).108... 

Alkenylsilanes, mainly vinyl silanes and allyl silanes or related compounds, being widely used intermediates for organic synthesis can be efficiently prepared by several reactions catalyzed by transition-metal complexes, such as dehy-drogenative silylation of alkenes, hydrosilylation of alkynes, alkene metathesis, silylative coupling of alkenes with vinylsilanes, and coupling of alkynes with vinylsilanes [1-7]. Ruthenium complexes have been used for chemoselective, regioselective and stereoselective syntheses of unsaturated products. 

As we have already mentioned, ruthenium complexes predominantly catalyze the dehydrogenative silylation of alkenes but competitively with the hydrosilylation so the reaction usually gives a mixture of the dehydrogenative silylation and hydrosilylation products. Ru3(CO)12 appears to be a very active catalyst for the dehydrogenative silylation of styrene, para-substituted styrenes [ 19, 20],trifluoropropene and pentafluorostyrene [21] by trialkyl-, phenyldialkyl-silanes (but also triethoxysilane) (Eq. 10). 

Cyclic seven-membered vinyl silanes 161 were obtained by regio- and stereoselective hydrosilylation of internal alkynes catalyzed by the ruthenium complex [Cp Ru(MeCN)3]PF6, as shown in Equation (33) <2005JA10028>. Hydrosilylation of 2,2-divinyladamantane with bis(hydrosilane) species 162 in the presence of Zeise s dimer [Pt2Cl4(CH2CH2)2] gave the disilacyclic 163 in high yields (Equation 34) <19980M4267>. 

Since 1957 and the discovery of the Speir s catalyst H2PtCl6/ PrOH, considerable efforts have been made to find new catalysts with high activity and selectivity. Along with the platinum-based catalysts, the Wilkinson s complex [103] Rh(Ph3P)3Cl is one of the most popular hydrosilylation catalysts. Ruthenium catalysts are also able to promote the addition of silanes to unsaturated carbon-carbon bonds, and several reports have shown during the past decade that the well-defined ruthenium complexes of type Ru(H)(Cl)(CO)L can provide excellent activity and selectivity [104—... 

Previous reports on the reaction of vinyl-substituted silanes [9] and silsesquioxane [15] with vinyl allQrl ethers catalyzed by ruthenium complexes containing or generating Ru-H and/or Ru-Si bonds show that the process proceeds according to the nonmetallacarbene mechanism as in SC and yields (usually in 5-fold excess of alkene) l-silyl-2-alkoxy-ethenes with a high preference for the E-isomer (Eq. 1). 

The two reactions catalyzed by ruthenium complexes, i.e. silylative coupling (SC) (trans-silylation) catalyzed by I, II, V, and VI and cross-metathesis (CM) (catalysts III and IV) of vinyl- and allyl-substituted hetero(N,S,B)organic compounds with commercially available vinyltrisubstituted silanes, siloxanes, and silsesquioxanes provide a universal route toward the synthesis of well-defmed molecular compounds with vinylsilicon functionality. 

CtH,ftN4, 1,2-Ethanediamine, N,N,N, N -te-tramethyl-, lithium complex, 26 148 C Hi Si, Silane, triethyl-, ruthenium complex, 26 269... 

Supported platinum, rhodium, and ruthenium complex catalysts have been used extensively in the reaction of trisubstituted silanes with acetylene in the gas phase, predominantly in a continuous-flow apparatus. Formation of a polymer layer on the surface after immobilization of the platinum complex has protected the catalyst against leaching in long-term hydrosilylation tests [91]. 

C5H15O3P, Triethyl phosphite, iron complex, 26 61, 28 171 nickel complexes, 28 101, 104-106 CjHijP, Phosphine, triethyl-, gold-osmium complexes, 27 209, 211 gold-platinum complex, 27 218 nickel complex, 28 101 platinum complexes, 26 126, 135-140, 27 32, 34,28 27, 120, 122, 133, 29 191 C5H16N4, l,2-Ethanediamine,AfJVJV Af -tetramethyl-, lithium complex, 26 148 CjH,6P2, Phosphine, l,2-ethanediylbis(di-methyl-, nickel complex, 28 101 CjHijSi, Silane, triethyl-, ruthenium complex, 26 269... 

With certain ruthenium complexes sueh a [RuCl2(p-eymene)]2, allyltrisubstituted silanes (allyltrimethylsilane, allyltriethoxysilane) undergo isomerization to the corresponding 1-propenyltrisubstituted silane followed by cross-metathesis between the two isomers (Marciniec 1994a). 

DFT methods are also used to analyze a bis(silane)ruthenium complex, RuHj-[(SiHMe2)2X](PR3>2 [X = o-phenylene, see Eq. (11.7)]. Although the Si-H units... 

In 2007, synthesis and complexation of a PSiP-pincer hgand, in which a sihcon atom and two phosphorus atoms are tethered by a phenylene group, was first reported by Turculet and coworkers [11-19]. They reported that the PSiP-ruthenium complex exhibited catalytic activity for transfer hydrogenation of ketones [11], and the PSiP-platinum and -palladium complexes efficiently catalyzed reduction of COj to methane by silanes [18[. Shortly after the Turculefs first report in 2007, we reported the first example of utilization of the phenylene-bridged PSiP-pincer complex in carbon-carbon bond formation reactions of unsaturated hydrocarbons [20[. 

Diallylsubstituted silanes undergo polycondensation in the presence of ruthenium complexes via preliminary catalytic isomerization to vinylsilane(s). This is followed by their (poly)co-condensation to yield silylene-propenylene polymers containing nogem isomeric fragments. 

Effective disproportionation and co-disproportionation of vinylsilane with ruthenium complexes containing the Ru-H, Ru-Si bond, called subsequently silylative coupling or trans-si y aiion of olefins with vinylsubstituted silanes, was revealed in 1984 as a new synthetic route to substituted vinylsilanes and are commonly used as organic reagents. Subsequent extensive synthetic and catalytic study has shown that silylative coupling of olefins with vinylsubstituted silicon compounds occurs (similarly to the hydrosilylation and dehydrogenative silylation reactions) via active intermediates containing the M-Si (silicometallics) and the M-H bond (where M = Ru, Rh, Ir, Co, Fe). The insertion of olefin into M-Si bond and vinylsilanes into M-H followed by elimination of vinylsilane and ethane respectively, are the key steps in this new process. 

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