Hydrocarbon-metal reaction, carbon atom formation

Formation of products containing less than four carbon atoms is not related to the catalytic activity of the metal on the decomposition of hydroperoxides. Hence, the liquid-phase oxidation of hydrocarbons involves heterogeneous catalytic reactions of isomerization and decomposition of peroxide radicals, proceeding on the reactor surface. 

A relatively common interaction in molecular coordination or organometallic compounds that nominally are coordinately unsaturated is the formation of a three-center two-electron bond between a metal center in the compound and a C-H bond of a hydrocarbon, a hydrocarbon fragment, or a hydrocarbon derivative that is a ligand in the complex. This interaction can be the prelude, the intermediate or transition state, to a subsequent reaction in which the CH hydrogen atom is transferred to the metal center and a direct a bond is formed between the carbon atom and the metal atom especially if the C-H bond is an activated bond. Internal oxidative addition of CH is a term often applied to this subsequent reaction step. The overall sequence is schematically outlined in 1. Factors that materially... 

Ring expansion reactions of the type shown in equations (17) and (18), in which a more equitable distribution of carbon atoms between two rings of a polycyclic hydrocarbon is produced, provide the link between the decyclization reactions above and the annulation reactions considered later. It would seem that the greater the strain in the reactant, the larger the number of potential catalysts. The complexes of seven different metals catalyze the reaction shown in equation (17). Of the possible catalysts, only the silver (I) salts bring about any byproduct formation. The isomerization of [l.l.ljpropellane (equation 18) is catalyzed by [RhCl(PPh3)3]. ... 

In another reaction of [Mo3S4] +, its aqua complex [Mo3S4(H20)9] + reacts with acetylene at room temperature in I m HCl to yield complex 61, according to Scheme 20. Here a bond is formed between a carbon atom within a hydrocarbon molecule and a sulfur atom of a metal-sulfide cluster. The adduct can be viewed as representing the transition state or intermediate presumed to be formed when an organosulfur molecule reacts with a sulfide vacancy of a heterogeneous catalyst (cf. Section 2.6.4) or a cluster. However, whereas the reaction depicted in Scheme 20 is the first step of a sulfurization process (C-S bond formation), the direction of the conversion would have to be reversed to make it the second step of a desulfurization process (C-S bond cleavage). 

Carbon-carbon bond formation reactions are of critical importance to the Fischer Tropsch synthesis of linear hydrocarbons over transition metals such as Co, Fe or Ru. Fischer-Tropsch synthesis involves the activation of CO and H2 over the metal to form adsorbed carbon, oxygen and hydrogen. The carbon atoms that form hydrogenate to form... 

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