Homogeneous reactions catalyzed by organometallic compounds

Carbon dioxide is the supercritical solvent that is most commonly used in homogeneous catalytic reactions. In addition to being environmentally acceptable (nontoxic, nonflammable), inexpensive, and available in large quantities, carbon dioxide does not participate in most reactions. It also has an ambient critical temperature. Although, supercritical carbon dioxide is more effective in dissolution of non-polar, nonionic and low molecular mass compounds, addition of co-solvents enhances the solubility of many otherwise insoluble compounds in supercritical carbon dioxide. A recent review by Noyori et al. discusses homogeneous catalytic reactions under supercritical conditions. 

Asymmetric hydrogenation of tiglic acid Ruthenium catalyst 

Asymmetric hydrogenation of enamides Cationic rhodium complex 

Ring opening metathesis polymerization Ruthenium catalyst 

Ring closing metathesis of dienes to cyclic olefins Ruthenium catalyst 

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