Stereochemistry of Certain Catalytic Reactions of Cyclic Hydrocarbons in the Presence of Group VIII Noble Metals

The mechanisms of certain catalytic reactions in the presence of solid catalysts – mainly Group VIII noble metals – are discussed in the review. Attention has been concentrated on the stereochemistry of the reactions. It has been shown that the modern conformational hypotheses may be successfully employed to investigate the detailed mechanisms of a number of heterogeneous-catalytic reactions, in particular certain stereochemical reactions of cyclic hydrocarbons. The most widely adopted mechanisms of the hydrogenation of dialkylcyclo-olefins and also di- and poly-alkylbenzenes have been examined and discussed. Both types of reactions are genetically related and the proportions of the stereoisomers obtained serve in many cases as a definite criterion for the selection of a particular reaction mechanism. The configurational isomerisation of di- and poly-cycloalkanes – a reaction involving direct interconversion of the isomers – has been examined in detail. The direct involvement of hydrogen in this reaction, which at first sight appears to be unimolecular but is in fact bimolecular, has been demonstrated.
The bibliography includes 125 references.