Acetonitrile osmium complex

X10 cm /s. This is over 1,000 X smaller than the Hiffusion coefficient for this osmium complex diffusing freely in the acetonitrile solvent (obtained from the limiting current at the naked Pt electrode), and the observed PD corresponds to a very low permeability of the polymer film to luch bulky permeants. 

Two arene cyclopentadienyl osmium complexes of type 191 have been prepared in moderate yields (17-43%) by reacting precursor 144 with thallium cylopentadienide in acetonitrile (73). 

The complex Os(SCl0Hl3)4(CNMe) is made from OsCl3, the lithium salt of 2,3,5,6-tetramethyl-benzenethiolate and 2,3,5,6-tetramethylphenyl sulfide it is green-yellow. The X-ray crystal structure of the ruthenium salt shows it to be trigonal bipyramidal, with the acetonitrile in the axial position. The osmium complex is isomorphous it would seem therefore to be the only example so far reported of a trigonal bipyramidal osmium(IV) complex. In an attempt to make a complex of lower coordination number 2,4,6-triisopropylbenzenethiolate (SC15H23) was used but the complex was still pentacoordinate, i.e. Os(S15H23)4(MeCN).719... 

Acetonitrile, molybdenum and tungsten complexes, 26 122, 133 osmium complex, 26 290 palladium complex, 26 128 ruthenium complex, 26 356 ruthenium(II) complex, 26 69... 

C2H,N, Acetonitrile, cobalt, copper, and ruthenium complexes, 26 356, 359 molybdenum, palladium, and tungsten complexes, 26 128-133 osmium complex, 26 290, 292 ruthenium(II) complexes, 26 69-72 C2H4, Ethene, molybdenum complex, 26 102-105... 

As discussed above for ferrocene derivatives, small water-soluble ruthenium and osmium complexes are good candidates for redox enzyme catalysis mediation for their reversible (II/III) behavior and relative stabiKty in the two-oxidation state in water. The alteration of the aromatic rings is a means of tuning of the redox potential/structure characteristics of the complexes, which is important for efficient redox enzyme mediation [75, 76]. Table 1 gives the redox potentials in acetonitrile of a series of neutral osmium(II) dichloride complexes with different substituted ligands [77]. 

The reaction of the osmium complex 40 (R = Ph, CeHn) with acetonitrile affords the osmacyclopentapyrroles 41 in 83 % and 79 % yields, respectively . 

Table 3 Photophysical data of selected osmium(VI) 0x0 and nitrido complexes in acetonitrile at room...

The one-electron reduction of NP is associated with an increase in the population of the antibonding FeNO orbital. Figure 6a shows the DFT computed LUMO of NP (58), and Fig. 6b shows the IR electrochemical response for the [OsII(CN)5NO]2 ion (59) upon one-electron reduction in acetonitrile. The spectral characterization of the osmium-nitrosyl reduced complex could be done successfully because of the inertness of the Os-L bonds (L = NO or cyanide). In contrast, NP rapidly releases a cyanide ligand upon reduction in acetonitrile (57b,57d). The strong decrease of both the vqn and v o stretching frequencies in [Osn(CN)5NO]3 is very noticeable, particularly uN(> This is as predicted from the LUMOs description, since the addition of electrons to [OsII(CN)5NO]2 must weaken the NO bond. 

Photoinduced and chemical oxidation of coordinated imines to amides in isomeric osmium(II) complexes of AT-arylpyridine-2-carboxaldimines has been studied by Ghosh and coworkers [34]. The complexes [Os(Br)2(Rimpy)2] (Scheme 1) were prepared and characterized structurally, indicating the pyridines of the two Rimpy ligands are trans to one another and the bromides are cis. Broadband photolysis of the complex in aerated acetonitrile resulted in oxidation of one Rimpy ligand to yield the RimOpy ligand and oxidation of the osmium to Os(III). The overall yield of the photochemical process is reported to be greater than 95%. The authors propose a mech-... 

Not only N, but also C atoms can take part as donor centers in azacymantrene 760 (E = N, R = H) and azaferrocene 763 (R = H). In this respect, the formation of a trinuclear osmium-carbonyl adduct 768 is representative, which takes place in the reaction of the indicated azacenes with acetonitrile complex of triosmium decarbonyl [482] ... 

Photophysical Data of Selected Osmium(VI) Oxo and Nitrido Complexes in Acetonitrile at Room Temperature... 

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