1- Propene, ruthenium complex

The hydroarylation of olefins is also achieved by using a ruthenium catalyst, TpRu(CO)(NCMe)(Ph) (Tp = hydridotris(pyrazolyl)borate) (Equation (34)).39 The reaction of benzene with ethene is catalyzed by the ruthenium complex to give ethylbenzene (TN = 51, TOF = 3.5 x 10 3mol 1 s-1 at 90 °G for 4h). The ruthenium-catalyzed reaction of benzene with propene gives the hydroarylation products with a 1.6 1.0 ratio of -propyl to isopropylbenzene, with 14 catalytic turnovers after 19 h. 

The hydroformylation of alkenes to give linear aldehydes constitutes the most important homogeneously catalyzed process in industry today [51]. The hydroformylation of propene is especially important for the production of n-bu-tyraldehyde, which is used as a starting material for the manufacture of butanol and 2-ethylhexanol. Catalysts based on cobalt and rhodium have been the most intensively studied for the hydroformylation of alkenes, because they are industrially important catalysts. While ruthenium complexes have also been reported to be active catalysts, ruthenium offers few advantages over cobalt or... 

C4H6O2, Acrylic acid, methyl ester ruthenium complex, 24 176 C4H8, 1-Propene, 2-methyI-iron complexes, 24 161, 164, 166 C4H l4N5P3, l,3,5,2X ,4 ,6 -Triazatri-phosphorine... 

Reaction of the dinuclear ruthenium complexes, XXV, with propene gives n-allylruthenium complexes, XXVI. A mechanism is shown in Scheme 3. 

The ruthenium complex 106 is capable of cleaving the C-C bond through jS-allyl elimination in tertiary homoallylic alcohols to give the ketones 207 and propene 208 (Scheme 95) [133]. 

The reaction of 1-aryl-2-propynols (propargylic alcohols) with HP(0)Ph2 in the presence of dinuclear ruthenium complexes 30 produces 2,3-bis(diphenyl-phosphino)propene derivatives in high yields (Scheme 44) [45]. 

Tungsten hexachloride and molybdenum pentafluoride desulfurize 2-methylthiirane to propene (72DOK(207)899) and a ruthenium(II) complex desulfurizes thiirane (73JA4758). 

The double phosphinylation of propargylic alcohols with diphenylphos-phine oxide to form 2,3-bis(diphenylphosphinyl)-1-propenes is catalyzed by a thiolate-bridged diruthenium complex (Scheme 28) [69]. It has been shown that the reaction proceeds via three ruthenium-catalyzed transformations propargylation of the phosphine oxide, alkyne to allene isomerization, and addition of phosphine oxide to the allene structure. 

It is well known that silylation of allyl derivatives with vinylsilane catalyzed by a ruthenium hydride complex is accompanied by isomerization ofpropen-l-yl to propen-2-yl derivatives as well as homo-coupling of vinylsilane when equimolar amounts of the initial substances are used. If catalyst I was used in the SC of allyl amide and allyl amine with vinylsilanes, a S-fold excess of olefin to vinylsilane was used to stop homocoupling of vinylsilane, but simultaneously no more than 5% of isomerization of allyl compound was observed [19, 26]. When allyl boronate is used instead of allylamine under mild conditions (20 - 40 °C), the two reactions catalyzed by I and IV yield stereoselectively -product (see Scheme 4) [26]. 

The inactivity of Ru-H (and Ru-Si) complexes in the SC of allyl sulfides with vinylsilanes is due to analogous formation of ruthenium sulfide, reported previously [27], and elimination of propene according to the following equation. 

The challenging photochemical reduction of carbon dioxide to formate is catalyzed by Ru" [111] (cf. Section 3.3.4). For example, with the 2,2 -bipyridine-ruthenium(II) complex the active species is formed by photolabilization. Water renders the system more efficient with quantum yields up to 15%. Methanol is the photoproduct when CO2 is reduced with Ti02 in propene carbonate/2-propanol... 

Carbonyl complexes of rhodium, ruthenium, osmium, iridium, and platinum, in the presence of H2O and a weak base (e.g., trimethylamine), act as catalysts for the conversion of propene to a mixture of butanol and methylpropanal with the exception of the platinum system, these catalysts are considerably more active than Fe(CO)s as reported by Reppe. Under the same conditions, but in the absence of olefin, the carbonyls act as catalysts for the conversion of CO and H2O to CO2 and H2. The metal carbonyls, together with Fe(CO)s, in the presence of H2O, CO, and a weak base such as McsN, serve as catalysts for the conversion of nitrobenzene, dinitrobenzene, and 2,4- and 2,6-di-nitrotoluene to the corresponding aminobenzene derivatives. 

Other reversible y6-alkyl eliminations cause the transformation of ruthenacy-clobutanes to methyl allyl ruthenium derivatives (Eq. 6.26) [152], or alkyl exchange by a rare formal -alkyl elimination in a metal alkenyl complex (Scheme 6.52) [153]. Reversible propene extrusion by /1-alkyl elimination has also been described for some zirconium metallacycles [154]. 

Upon collisional activation, these ions lose masses of 27 and 41, respectively, restoring the original propene complex. Mass selection of different ruthenium isotopes confirms these assignments. 1-Butene reacts with ruthenium... 

The generally accepted mechanism for olefin cross-metathesis is outlined for the case of propene in Mechanism 14.4. The catalyst belongs to a class of organometallics known as a metallocarbene, carbene complex, or alkylidene complex. Its structure is characterized by a carbon-metal double bond. In olefin metathesis the metal is typically ruthenium (Ru), tungsten (W), or molybdenum (Mo). Transition-metal carbene complexes were first prepared by Ernst O. Fischer (Munich) who shared the 1973 Nobel Prize in Chemistry with Geoffrey Wilkinson. 

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