Nitrosyl ammines

The hexamine cobalt (II) complex is used as a coordinative catalyst, which can coordinate NO to form a nitrosyl ammine cobalt complex, and O2 to form a u -peroxo binuclear bridge complex with an oxidability equal to hydrogen peroxide, thus catalyze oxidation of NO by O2 in ammoniac aqueous solution. Experimental results under typical coal combusted flue gas treatment conditions on a laboratory packed absorber- regenerator setup show a NO removal of more than 85% can be maitained constant. 

At increasing temperatures in the presence of only zeolite hydration water, Ru-Red is transformed into a Ru(II)nitrosyl-ammine moiety, using the assignments of previous work (7 8)... 

Nitrosyl ammine intermediates have been detected when [Ru(NH3)6]3+ is treated with 02 in... 

NH3)5P" is scavenged by O2 with a rate constant k = 1.6 x lO M s Nitrosyl ammine intermediates have been detected when [Ru(NH3)ft] is treated with O2 in... 

Nitrosyl ammine, amine, heterocyclic and phosphine complexes are discussed in Sections 45.4.1, 45.4.2, 45.4.3 and 45.5 respectively. A range of nitrosyl complexes incorporating NO and NOj" ligands have been reported. Treatment of RUCI3 with NaN02 yields [Ru(0H)(N02)4(N0)] ... 

Neutral and Cationic Ligands. Neutral and cationic ligands are used without change in name and are set off with enclosing marks. Water and ammonia, as neutral ligands, are called aqua and ammine, respectively. The groups NO and CO, when linked directly to a metal atom, are called nitrosyl and carbonyl, respectively. 

The carbonyl complex [Ru(EDTAH)(CO)] has been reported to be a very good catalyst for reactions like hydroformylation of alkenes, carbonylation of ammonia and ammines as well as a very active catalyst for the water gas shift reaction. The nitrosyl [Ru(EDTA)(NO)] is an oxygen-transfer agent for the oxidation of hex-l-ene to hexan-2-one, and cyclohexane to the corresponding epoxide. 

Neutral ligands, such as H2NCH2CH2NH2 (ethylenediamine), have the same name as the molecule, except for HzO (aqua), NH (ammine), CO (carbonyl), and NO (nitrosyl). 

Neutral ligand names, with the exception of NH3 (ammine), H20 (aqua), CO (carbonyl) and NO (nitrosyl), are expressed in coordination nomenclature by their unmodified names. The ligand names for all neutral ligands except for the four listed above are enclosed in punctuation (parentheses - ( ), square brackets - [ ], and braces - ). For examples see Table 3. 

There are now a substantial number of nitrido complexes of osmium(VI) and osmium(IV) as well as the osmiamate ion [OsVII 03N]. In addition to the ammine and ethylenediamine complexes, much recent work has been carried out on the bipy, phen and terpy complexes, often in connection with research into the photodissociation of water. The nitrosyl chemistry of the element, though seemingly not as extensive as that of ruthenium, has received much attention, and there has been considerable work on the phosphine, arsine and stibine complexes. 

Until recently ammine complexes of osmium have been little studied compared with their ruthenium analogs. This appears to have been caused by the lack of suitable synthetic routes to them. The discovery of pentaammine(dini-trogen)osmium (II) opened convenient routes to pentaammines of osmium (III), and a convenient synthesis of hexaammineosmium(IIl)2 gave new routes to the previously unknown nitrosyls of osmium(II). Here are given the synthesis of [Os(NH3)s(N2)]l2 and its conversion to [Os(NH3)5l]l2 the synthesis of [Os(NH3)6]l3 and its conversion to [Os(NH3)5(NO)]X3 H20(X = Cl, Br, I) and the preparation of [OsX(NH3)4(NO)]2+(X = OH, Cl, Br, I) from [Os(NH3)5(NO)]3+. 

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. ... 

All ligands receive a separate subject entry, e.g., 2,4-Pentanedione, iron complex. The headings Ammines, Carbonyl Complexes, Hydride complexes, and Nitrosyl complexes are used for the NH, CO, H, and NO ligands. 

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