Nickel dimethylsulfoxide

Tetraazamacrocyclic complexes131 of cobalt and nickel were found110 to be effective in facilitating the reduction of C02 at -1.3 to -1.6 V versus SCE (Table 8). An acetonitrile-water mixture and water were used as solvents, while in dry dimethylsulfoxide no catalytic reduction of C02 took place. Using an Hg electrode, both CO and H2 were produced, where total current efficiencies were greater than 90%. The turnover numbers of the catalysts were 2-9 h 1. The catalytic activity lasted for more than 24 h and the turnover numbers of the catalysts exceeded 100. A protic source was required to produce both CO and H2, and the authors suggested that both products may arise from a common intermediate, which is most likely a metal hydride. The applied potential for C02 reduction was further reduced by using illuminated p- Si in the presence of the above catalysts.111... 

Octakis (dimethylsulfoxide) nickel (II) Diperchlorate. (Me2S0)8Ni++.2C104 C16H48Cl2-NiOj 6S8 mw 878.87 OB to C02, NiO SO —81.0% a cryst solid, explds from 200—35°... 

Scheme 12.23. Synthesis of burseran using a three-component conjugate addition/Wacker-type cyclization, by Balme and co-workers [79]. DMSO = dimethylsulfoxide, THF = tetrahydrofuran, Ra-Ni = Raney nickel.

The electrochemistry of the polymeric and isomorphous cobalt(II) and nickel(II) methylsquarates was also studied by Iwuoha et al. In aqueous solutions, they found evidence that both the nickel(II) methylsquarate and its cobalt analog were dissociated without any reversible redox processes occurring for the metal ions. However, the cyclic and Osteryoung square wave voltammograms, obtained using a Pt electrode for solutions of these complexes in dimethylformamide and dimethylsulfoxide, contained signals attributable to both ligand-based and metal-based redox processes 142). 

It was found that addition of hydroxide anion in dimethylformamide or dimethylsulfoxide to metal(II) corrole complexes results in the appearance of much sharper absorption bands relative to the starting compounds. These findings were considered consistent with the idea that an anionic, 18 Jt-electron aromatic corrole complex (e.g., 2.119) is formed as the result of what appears to be a formal deprotonation process (Scheme 2.1.25). That deprotonation actually occurs was inferred from acid-base titrations involving nickel(II) and copper(II) corroles. The conclusion that these species are anionic aromatic compounds came from an appreciation that their electronic spectra resemble those recorded for divalent metallo-porphyrins. In any event, the anion that results was found to be quenched upon acidification, regenerating the corresponding non-aromatic metallocorroles. ... 

Dimethylsulfoxide was found to increase the rate of hydrolysis in esters which were resistant to saponification. Treatment of alkyl toluenesulfonates with sodium naphthalene anion radical in tetrahydrofuran constituted an almost ideal procedure for regenerating the corresponding alcohols. The hydration of nitriles to amides in the presence of nickel catalysts shows an increase in yield with the addition of pyridine. ... 

The tautomerism is driven by the increased basic strength of 3-aminophthalate in the aprotic solvent with the resultant structural change decreasing the energy of lowest excited singlet state. The kinetics of the reaction in dimethylsulfoxide are first order with respect to the concentrations of hydroxide, oxygen, and luminol. An important analytical feature is the catalytic effect of certain transition metal cations upon the reaction shown in Scheme 4. The luminescence intensity is proportional to the concentration of species including cobalt(II), copper(II), chromium(III), iron(II), and nickel(II) at levels down to 10 moll . ... 

Anhydrous nickel(II) chloride in nitromethane, containing a stoichiometric amount of CaL, yields a light green solution. When the temperature is raised, an intense blue color develops this suggests the existence of an equilibrium similar to the one observed for nickel(II) chloride solution in dimethylsulfoxide. ... 

C3 2H5 2N4O1oPd2S4, (N(a)-Salicylidene-D-ornithinato)(N(a)-salicyl-idene-L-ornithinato)dipalladium(II)-dimethylsulfoxide, 42B, 754 C3 3H3oCl2Fe2N40s, /Lt-Oxo-bis(N,N -ethylenebis(salicylideneiminato)-iron(lll)) - dichloromethane, 37B, 497 C33H31CI2CUN3O2 f (3,3 -Dichloro-2,2 -(1,12-diphenyl-2,6,11-triaza-dodeca-1,11-diene-1,12-diyl)bis(phenolato))copper(II), 45B, 1074 C33H3 tCl2N3Ni02 f (3,3 -Dichloro-2,2 -(1,12-diphenyl-2,6,11-triaza-dodeca-1,11-diene-1,12-diyl)bis(phenolato))nickel(II), 45B, 1074 C3 4H2 4CUN2O2 r Bis(N-phenyl-2-hydroxy-1-naphthylideneiminato)copper-(II), 44B, 843... 

C2aH 2 6N2Ni07SU, Nickel(ll) (3,8-dimethyl-4,7-diazadeca-2,8-diene-1,1O-dione-1,10-di(o-phenolato))uranyl dimethylsulfoxide, 44B, 1005 C2 H2 eCr2N80ij CgHiijOa, Tetrakis(2,4-dimethyl-6-hydroxypyrimidino)-dichromiumdl) 2,2 -dimethoxydiethylether solvate (form A), 45B, 1273... 

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