Coordination compounds, cobalt 186, ruthenium

Among the most significant developments in the field of catalysis in recent years have been the discovery and elucidation of various new, and often novel, catalytic reactions of transition metal ions and coordination compounds 13, 34). Examples of such reactions are the hydrogenation of olefins catalyzed by complexes of ruthenium (36), rhodium (61), cobalt (52), platinum (3, 26, 81), and other metals the hydroformylation of olefins catalyzed by complexes of cobalt or rhodium (Oxo process) (6, 46, 62) the dimerization of ethylene (i, 23) and polymerization of dienes (15, 64, 65) catalyzed by complexes of rhodium double-bond migration in olefins catalyzed by complexes of rhodium (24,42), palladium (42), cobalt (67), platinum (3, 5, 26, 81), and other metals (27) the oxidation of olefins to aldehydes, ketones, and vinyl esters, catalyzed by palladium chloride (Wacker process) (47, 48, 49,... 

Another series of model compounds is based on cobalt weyo-tetra(4-pyridyl) porphyrins with four [Ru(NH3)5] " or [Ru(edta)] groups (electron donors) coordinated to the peripheral V-pyridyl atoms (117-119). Such species exhibited faster ET kinetics because the four ruthenium complexes can act as reservoirs and CT relays for electron exchange with the electrode surface (118). However, it was shown that the peripheral complexes do not change the two electron reduction mechanism (353). 

---