Ruthenium ethenes, preparation

Methyl />-tolyl sulfone has been prepared by oxidation of methyl 7>-tolyl sulfide with hydrogen peroxide 4 r or ruthenium tetroxide,6 by alkylation of sodium -toluenesullinate with methyl iodide 7,8 or with methyl potassium sulfate,9 by decarboxylation of -tolylsulfonylacetic acid,7 by thermal decomposition of tetramethylammonium -toluenesulfinate,10 by reaction of cw-bis-(%tolylsulfonvl)-ethene with sodium hydroxide (low yield),11 by the reaction of methanesulfonyl chloride with toluene in the presence of aluminum chloride (mixture of isomers),12 by... 

Vinylsilanes have proved to be of some small interest because, as noted earlier, it appears that the silyl group stabilizes carbocations p to the position bearing the silicon. Trimethylvinylsilane [(013)301=012] is generally prepared, as shown in Equation 10.85 by the reaction between trimethylsilane [(CH3)3SiH] and ethene (ethylene, H2C=CH2) over an iron(V) pentacarbonyl [Fe(CO)s] catalyst. Interestingly, the corresponding trichlorovinylsilane (Cl3SiCH=CH2) can also be made in a condensation reaction. In this case (Equation 10.86), the reaction is between ethyne (acetylene, HC=CH) and trichlorosilane in the presence of a ruthenium dichloride (RuCb) catalyst. 

Thermolysis of [Ru(PPh3)3(GO)H2l first with a stoichiometric amount of GH2=GHPh, and then with a stoichiometric amormt of < -acetylstyrene, yields the alkene complex The fluxional, five-coordinate Ru(0) ethene complex [Ru(PPh3)3(GO)( 7 -G2H4)] was readily prepared by refluxing the same ruthenium dihydride precursor under a flow of ethene.A range of alkene complexes [RuLL (GO)2( -alkene)] L = L =PMc2Ph, AsMe Ph,... 

Hydrosoluble iridium alkyl complexes may also be prepared by hydrolysis of alkynes and alkenes promoted by water-soluble precursors. The reaction with alkynes follows the well-known mechanism demonstrated by Bianchini et al. for ruthenium complexes.A reasonable mechanism, related to that of hydrolytic breakage, has been proposed by Chin etal. to account for the hydrolysis of ethene promoted by [Cp"lr(TPPMS)Cl2] 344 in the presence of silver salts in water. Scheme 37 describes the Chin s hydrolysis of alkynes, leading to [Cp Ir(TPPMS)(CO)(CH2R)] (69 R=Ph, Bz, Bu, />-Tol) via the aquo complex [Cp Ir(TPPMS)(OH2)OTf 345... 

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