Nitrosyl cyano complexes

K4Ni(CN)4 is a yellow solid which is extremely sensitive to oxygen and moisture. It can be prepared by reducing K2Ni(CN)4 in liquid NH3 with an excess of potassium17 and decomposes in water with H2 evolution. CN ions can be easily replaced by ligands with greater jt acceptor properties such as CO, NO and phosphines. Mixed carbonyl and nitrosyl cyano complexes have been prepared by direct reactions (equations 1 and 2).18,19... 

Nitrosyl Cyano Complexes. Although they are not basically different from other nitrosyl complexes, [M(CN)5NO] 1- species have generally received special attention. Those studied by X-ray crystallography have octahedrally coordinated metal atoms and linear MNO groups. These... 

Only a limited number of cyano and isocyano complexes and mixed carbonyl, nitrosyl and phosphine cyano complexes of nickel(O) have been described so far.16... 

Formation of Ni(CO)4 or Co(CO)4- by the cyanide method depends upon the stepwise substitution of the anion of the cyano complex by the iso-electronic carbon monoxide molecule. By treating Co2(CO)8 with potassium cyanide we obtained cyanocarbonyls of cobalt of low oxidation number (83). In reactions of the nitrosyl carbonyls of iron and cobalt, Behrens (86) substituted all the CO groups with CN to give K3[Co(NO)(CN)3] or... 

The cyano complexes of cobalt(—I) are restricted to nitrosyl and carbonylnitrosyl mixed ligand complexes, all of which obey the 18-electron rule. 

Irradiation of the Cr complexes [CrCCNlg] and [Cr(CN)6-x(OH),] (where x = 1, 3, or 6) in alkaline media has been described. Ligand photosubstitution by OH and oxidation to Cr both occur and in the case of [Cr(CN)s(H20)] and [Cr(CN)3(H20)3], photoaccelerated aquation is ob-served. " [CrL(CN)2(H20)]"- (where H4L = EDTA) also undergoes CN photoaquation, probably because labilization of other ligands is blocked or alternatively is not observable under the experimental conditions. This finding should be contrasted with the behaviour of cyano-ammine complexes which show primarily NH3 photoaquation.A complex photosubstitution occurs in the case of the nitrosyl complex [Cr(CN)5NO] and is followed by secondary thermal transformations to produce hydroxo-complexes of Cr . In the presence of oxygen, Cr04 ions are also formed. ... 

Manganates, hexachloro-, 58 Manganates, tetraalkyl-, 13 Manganates, tetrahalo-, 59 Manganates, tetraoxo-, 109 Manganates, trihalo-, 59 Manganese complexes, 1-111 carbonyl-nitrosyl, 7 cyano-nitrosyl. 8 electronic spectra, 4 lability, 6... 

At the time we reported the pK for [Fe(CN)5HNO], we had payed no much attention to our own previous computational DFT result predicting that [Fe(CN)5NO] was an unstable species that should lose CN from the coordination sphere, in contrast with the successfial predictions on the stabihty of other 5C and 6C cyano-nitrosyl complexes (12). Anyway, we considered a plausible decomposition route for the putative [Fe(CN)5NO]" intermediate, involving the frans-labdization of cyanide (Equation 30) ... 

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