Olefin complexes group 11 metals

This observation may well explain the considerable difference between metal-olefin and metal-acetylene chemistry observed for the trinuclear metal carbonyl compounds of this group. As with iron, ruthenium and osmium have an extensive and rich chemistry, with acetylenic complexes involving in many instances polymerization reactions, and, as noted above for both ruthenium and osmium trinuclear carbonyl derivatives, olefin addition normally occurs with interaction at one olefin center. The main metal-ligand framework is often the same for both acetylene and olefin adducts, and differs in that, for the olefin complexes, two metal-hydrogen bonds are formed by transfer of hydrogen from the olefin. The steric requirements of these two edgebridging hydrogen atoms appear to be considerable and may reduce the tendency for the addition of the second olefin molecule to the metal cluster unit and hence restrict the equivalent chemistry to that observed for the acetylene derivatives. 

The seminal report of an asymmetric homogeneous metal-catalyzed reaction described the copper-catalyzed group-transfer reaction from a diazoester to an alkene, Eq. 3 (2). This article provided experimental verification of the intervention of copper carbenoid olefin complexes in the catalytic decomposition of diazo com-... 

The work on complexes of metals of other groups with olefinic tertiary phosphines and arsines has until recently been neglected, but it has now become dear that the chelating properties of these ligands are almost as widespread as those of the more well known bis(phosphine) and bis(arsine) ligands, such as diphos and diarsine. 

This preparation is an illustration of the hydroformylation of olefins (oxo synthesis). The reaction occurs in the presence of soluble catalytic complexes containing metals of Group VIII of the periodic system. Although the metal originally used by Roelen and still largely used in the industry for the production of aliphatic aldehydes and alcohols is cobalt, the most active and selective catalysts are rhodium-containing compounds. The catalytic activity of the other Group VIII metals is in... 

Concerning Dr. Heck s expectation of a cis addition for the insertion reaction, we have found that the reverse reaction, an elimination, also results in a cis product. Thus, the isomerization of terminal olefins, catalyzed by metal ions which form ir-complexes, produces the cis-2 olefin first (4). Subsequently, the trans-2 olefin is formed, however, which requires explanation. Possibly the hydride is, in this case, pulled off the alkyl group by another coordinated olefin rather than by the metal itself. 

Both conjugated and nonconjugated olefins form complexes with the transition-metal carbonyls. Despite the fact that the first known complex, Zeises salt K(PtC2H4Cl3), discovered in 1827, was that of a simple olefin, complexes of monoolefins are rather limited in number. However, nonconjugated diolefins (L) react with group-VI carbonyls to form complexes of the type LM(CO)4 an example is provided by tetracarbonyl-bicyclo-(2,2, l)hepta-2,5-diene chromium (2) (Fig. 1). In contrast, the iron carbonyls... 

Olefins - [FEEDSTOCKS - COALCHEMICALS] (Vol 10) - [FEEDSTOCKS-PETROCHEMICALS] (VollO) - [HYDROCARBONS - SURVEY] (Vol 13) -m automobile exhaust [EXHAUSTCONTROL, AUTOMOTIVE] (Vol 9) -catalyst for stereospeafic polymerization [TITANIUMCOMPOUNDS - INORGANIC] (Vol 24) -esters from [ESTERIFICATION] (Vol 9) -hydroxylation using H202 [HYDROGEN PEROXIDE] (Vol 13) -luminometer ratings [AVIATION AND OTHER GAS TURBINE FUELS] (Vol 3) -osmium oxidations of [PLATINUM-GROUP METALS, COMPOUNDS] (Vol 19) -polymerization [SULFONIC ACIDS] (Vol 23) -reaction with EDA [DIAMINES AND HIGHER AMINES ALIPHATIC] (Vol 8) -silver complexes of [SILVER COMPOUNDS] (Vol 22)... 

Schiff bases -alkanolamines [ALKANOLAMINES - ALKANOLAMINESFROM OLEFIN OXIDES AND AMMONIA] (Vol 2) -from benzaldehyde [BENZALDEHYDE] (Vol 4) -platinum-group metal complexes of [PLATINUM-GROUP METALS, COMPOUNDS] (Vol 19)... 

Hydrosilylations of fluorine-containing alkenes are free radical reactions initiated by UV light or organic peroxides The direction of addition is the same as with fluonnated alkyl halides However, the reaction between hydrosilanes and fluorine-containing olefins catalyzed by platinum group metal complexes may result in bidirectional addition and/or formation of a vinylic silane, the latter by de hydrogenative silylation[/] The natures of both the silane and the catalyst affect the outcome of the reaction[7] A random selection of some typical new reactions of silanes are shown in Table 1 [1, 2, 3 4]... 

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