Manganese complexes nitrosyls

Neutral (cyclohexadienyl)manganese complexes 71, generated by nucleophilic addition to (arene)Mn(CO)3+ cations 65, undergo ligand substitution with nitrosyl hexafluorophosphate to give the corresponding (cyclohexadienyl)Mn(CO)2NO+ cations 72 (Scheme 17)93. Attack by a wide variety of nucleophiles on cations 72... 

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... 

Calderon JL, Cotton FA et al (1971) Molecular structure of an unusual binuclear manganese complex with highly unsymmetiical nitrosyl bridges. J Chem Soc D 1476-1477... 

Wang X, Zhou M, Andrews L (2000) Manganese carbonyl nitrosyl complexes in solid argon infrared spectra and density frmctional calculations. J Phys Chem 104 7964-7973... 

The first transition metal complex containing four different substituents to be resolved was the manganese complex shown in Scheme 2, top [6,7]. In the cation of this complex, the Mn atom is surrounded by a cyclopentadienyl, a carbonyl, a nitrosyl, and a triphenylphosphine ligand. This complex can be prepared from the commercially available compound (C5H5)Mn(CO)3 in two steps yielding [(C5H5)Mn(CO)(NO)PPh3]PF6 as a racemate [8]. 

Complexes of manganese with the 1,1-dithiolates have been restricted to the (PrSN)3[Mn(i-mnt)3] complex (112) and nitrosyl or carbonyl derivatives, e.g., [7i--CpMn(NO)(S2C==X)] (X = C(CN)C02Et, C(CN)C0NH2, NCN, C(CN)2, or (HNO2) (110, 204, 205). These complexes undergo electrochemical, one-electron oxidations and reductions to afford the neutral or dianionic species. 

Manganese nitrosyl porphyrins [215] are considered good models for the iron-nitric oxide analogs, which are relatively unstable but very vital to many biological operations. A six-coordinate manganese nitrosyl porphyrin of the form (por)Mn(NO)(L), where por can be TTP (TTP = tetra(4-methylphenyl)porphine) and L = piperidine, methanol, 1-methyhmidazole, has been prepared [216] in moderate yields by the reductive nitrosylation of the (por)MnCl complex with NO in piperidine. The crystal structures of these compounds give indication of a linear Mn-NO bond [215]. 

As has been deseribed, the parent monoearbollide-metal earbonyl piano-stool species [2-(CO) -c/oi o-2,l-MCBioHii] are now known for all of the metals M = Mo (12), W (13), Re (14), Fe (11), Ru (6), Os (8), and Ni (18). Evidence also exists for a diearbonyl-platinum analogue of eompound 18, ° and as mentioned earlier, the manganese analogue of 14 has also briefly been reported. A notable absenee from this list, however, is any representative of the Group 9 metals. The earbonyl nitrosyl-cobalt complex 21 is very elosely related to the hitherto unknown dicarbonyl-cobalt dianion [2,2-(CO)2-c/oi o-2,l-CoCBioHii] and this species remains an attractive synthetie target. 

Manganese-gallium bonds, formation, 5, 764-765 Manganese isonitriles, synthesis and characteristics, 5, 773 Manganese-nitrogen bonds, in Mn carbonyls, 5, 766 Manganese nitrosyl complexes, synthesis and characteristics, 5, 773... 

Nitrosyl-aryl porphyrin complexes, with iron, 6, 107 Nitrosyl complexes with chromium, 5, 301 with manganese, 5, 773... 

NO adds reversibly to reduced cobalamin, Cbl(II).156 It does not react directly with aquacobalamin(III), (0blni(H2O)), but it does add to Cbl,n(N02 ) and Cblm(NO).175 Acid hydrolysis of the dinitroso species releases nitrite, and binding of nitrite to Cblln(H20) generates Cbln,(. 02 ). This sequence thus affords a nitrite-catalyzed mechanism for NO substitution at Cblln(H20). The reaction of NO with Com porphyrins is quite complex.176 In the first step, NO displaces an axial water ligand to form a weakly bound mono NO complex this mono NO complex reacts with a second molecule of NO to form nitrite and a reduced Co-NO complex. This latter process is called reductive nitrosylation. Manganese(II) porphyrins bind NO very rapidly.177 Stability constants have been measured for the formation of mono and bis NO complexes of Cun(dithiocarbamate)2.157... 

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