Metal carbonyls nitrogen-donor complexes

Nitrogen-donor complexes of metal carbonyls, 10, 115-186 Nitrosyl complexes, 7, 211-236 Nitrosyl metal carbonyls, 7, 216-222 8, 21-22, 223... 

Formally, in each of these cases the disproportionation produces a positive metal ion and a metal ion in a negative oxidation state. The carbonyl ligands will be bound to the softer metal species, the anion the nitrogen donor ligands (hard Lewis bases) will be bound to the harder metal species, the cation. These disproportionation reactions are quite useful in the preparation of a variety of carbonylate complexes. For example, the [Ni2(CO)6]2 ion can be prepared by the reaction... 

Nitrile derivatives of the metal carbonyls have been discussed together with other nitrogen donor molecules in a number of contexts. Much of the early work has been reviewed by Manuel 337) in his article on Lewis base-metal carbonyl complexes in Volume 3 of this series, and by Stroh-meier 436) in his review of photochemical substitution reactions. In general, nitriles are weaker Lewis donors than phosphorus and nitrogen bases 436), but compared to carbon monoxide, better electron donors but poorer acceptors 427). Force constants and assignments for a series of complexes [(MeCN)jjM(CO)g J (M = Cr, Mo, W) were studied 165, 228, 296) and... 

The best known catalysts of the water gas shift reaction are the binary metal carbonyls ([Fe(CO)5], [M(CO)6] M = Cr, Mo, W [342,345-347]) and carbonyl clusters ([Ru3(CO)i2], [Rh fCO) ], [Ir4(CO)i2]) [347], In the basic solutions under 35-120 bar CO, elevated temperature (100-125 °C) is needed for reasonable catalytic activity. Often these complexes are used in solutions of nitrogen-containing bases (amines, pyridine or picolines) or the precursors are themselves complexes of N-donor ligands (substituted bipyridines and phenantrolines [348], pyridine, 2-, 3- or 4-picoline [349],... 

Orthometallated complexes are intermediates in numerous cyclic carbonylation reactions involving aromatics with nitrogen donor groups in their side chains. For example, aromatic ketoximes and azobenzene are carbonylated at elevated temperatures and pressures with a cobalt carbonyl catalyst to form five-membered ring heterocycles in which a carbonyl group has replaced the metal in the presumed orthometallated intermediate ... 

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