Catalytic reactions involving

Volume 15 Heterogeneous Catalytic Reactions Involving Molecular Oxygen by G.l. Golodets... 

All catalytic reactions involve chemical combination of reacting species with the catalyst to form some type of inteniiediate complex, the nature of which is the subject of abundant research in catalysis. The overall reaction rate is often determined by the rate at which these complexes are formed and decomposed. The most widely-used nonlinear kinetic equation that describes... 

In several papers dealing with catalytic reactions involving hydrogen and unsaturated hydrocarbons the observed self-poisoning of nickel or its alloys has been quite properly attributed to the presence of carbonaceous... 

Until now examples for catalytic reactions involving ferrates with iron in the oxidation state of -l-3 are very rare. One example is the hexacyanoferrate 8-catalyzed oxidation of trimethoxybenzenes 7 to dimethoxy-p-benzoquinones 9/10 by means of hydrogen peroxide which was published by Matsumoto and Kobayashi in 1985 [2]. Using hexacyanoferrate 8 product 9 was favored while other catalysts like Fe(acac)3 or Fe2(S04)3 favored product 10 (Scheme 2). The oxidation is supposed to proceed via the corresponding phenols which are formed by the attack of OH radicals generated in the Fe/H202 system. 

The proposed mechanism of the catalytic reaction involves the formation of the Cu(l) alkoxide 68 by displacement of either the chloride or the NHC from 65-67, followed by conversion to the hydride 69 by metathetical exchange of the tert-butoxide by the H of the silane (Fig. 2.10). 

Catalytic Reactions Involving Activation of O-H Bonds 205 1 mol% AgOTf... 

The second characteristic pertains to the fact that a very small amount of a catalyst may be able to maintain a high reaction rate over a long time. Although in practice some of the catalysts are extremely efficient for certain specific reactions, it is observed that in the majority of the cases of homogeneous catalysis, the enhancement in the reaction rate is proportional to the concentration of the catalyst used. In heterogeneous catalytic reactions involving reactant gases and solid surfaces, the total surface area of the solid may also affect the reaction rate. 

The overall catalytic reactions involved in the two step synthesis of hydroxymethyl ated PBD are given by Equations 1-6. It can be seen from reactions (1-6) that the addition of -CHO functional group can occur in three ways resulting in the formation of three types of hydroformyl ated PBD repeating units as shown by species A, B or C. Subsequent hydrogenation of units A, B and C result in the formation of hydroxymethylated PBD repeating units A, ... 

Many catalytic reactions involve the activation of Si—H bonds and consequently the reaction of silanes with platinum(0) has been studied extensively. The reactions of hydrosilanes with transition-metal complexes, including platinum, has been extensively reviewed by Corey and Braddock-Wilking.58... 

We have also underlined the potential of the OsHCl(CO)(P Pr3)2 complex in homogeneous catalytic reactions, showing that derived Os(t 2-H2) intermediates are formed under catalytic conditions. Stoichiometric and catalytic reactions involving the title complex have advanced together. 

In many cases, however, the interfacial area is not known, particularly when one is dealing with a heterogeneous catalytic reaction involving a liquid phase and a solid catalyst. Consequently, the following definitions of the reaction rate are sometimes useful. 

Catalytic reactions involving addition of two molecules of butadiene and hydrogen transfer from an acidic carbon atom (adjacent to a ir-allyl group) to the nickel oxygen bond were recently described (example 12, Table IV). 

W. S. Schneider, "Symposium of Homogeneous Catalytic Reactions involving Palladium. Division of Petroleum Chemistry, Inc. and Division of Inorganic Chemistry, Organometallic Subdivision, American Chemical Society, Minneapolis, Minnesota, 1969. 

Polymers Catalytic reactions involving C=C bonds are widely used for the conversion of unsaturated fatty compounds to prepare useful monomers for polymer synthesis. Catalytic C-C coupling reactions of unsaturated fatty compounds have been reviewed by Biermann and Metzger [51]. Metathesis reactions involving unsaturated fatty compounds to prepare co-unsaturated fatty acid esters have been applied by Warwel et al. [52], Ethenolysis of methyl oleate catalyzed by ruthenium carbenes developed by Grubb yields 1-decene and methyl 9-decenoate (Scheme 3.6), which can be very useful to prepare monomers for polyolefins, polyesters, polyethers and polyamide such as Nylon 11. 

It has been shown that the interpretation of catalytic reactions involving group VIII transition metals in terms of n complex adsorption possesses considerable advantages over classical theories by providing a link between theoretical parameters and chemical properties of aromatic reagents and catalysts. The concept has led to the formulation of a number of reaction mechanisms. In heavy water exchange the dissociative tt complex substitution mechanism appears to predominate it could also play a major role when deuterium gas is used as the second reagent. The dissociative mechanism resolves the main difficulties of the classical associative and dissociative theories, in particular the occurrence... 

A modification of an earlier procedure for debromination of v/c-dibromides in the presence of catalytic amounts of diorganotellurides has allowed the synthesis of terminal alkenes and cis- and frani-l,2-disubstituted alkenes from appropriate precursors the relative substrate reactivities suggest that, as for the stoichiometric reaction, the catalytic reaction involves intermediate bromonium ion formation. The Te(IV) dibromides formed in the debrominative elimination are reduced back to the catalysts by either sodium ascorbate or the thiol glutathione. 

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