Nitric oxide associative substitution

Fig. 7 General structme of 4-alkyl/aryl-2-(N-substituted aminoalkylamido) thiazoles associated with nitric oxide (NO) and glycosaminoglycans (GAGs) release inhibition...

The catalytic implications of the alternative coordination modes of nitric oxide in transition metal complexes were first noted by Collman (12). He argued that the linear bent transformation, concomitant with a change in the formal oxidation state of nitrogen from (III) to (I), results in the withdrawal of electron density from the metal center and facilitates the coordination of another ligand into a vacant site. Thus, the mixed carbonyl nitrosyl complex [Co(CO)3(NO)] undergoes thermal CO substitution by an associative mechanism, whereas the iso-electronic, homoleptic carbonyl [Ni(CO)4] reacts by a dissociative pathway (13). 

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