Cobalt hydride complexes carbonyl type

Most catalysts that have been mentioned so far are mononuclear. The few binuclear compounds utilized Co2(CO)8 or phosphinesubstituted derivatives) did not give evidence of any unusual type of binuclear catalysis. However, new products could result with catalysts producing two active centers in close vicinity which would not dissociate in the course of the reaction. The expected difference between mononuclear and binuclear catalysis is shown in the accompanying diagram (52). A series of metal salts of cobalt carbonyl hydride of composition M[Co(C0)4]n (M=Zn, Cd, Hg, n = 2 M = In, = 3) were tested as potential binuclear catalysts. The complex salts are relatively easily accessible Zn[Co(CO)4]2, for instance, may be prepared from cobalt carbonyl, metallic zinc, and CO (at 3000 psi initial pressure) using toluene as the solvent and a temperature of 200°. The compound may also be synthesized directly from metallic cobalt, zinc, and CO... 

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