Cobalt, determination derivatives

The photochemistry of cobalt-methyl derivatives of (3) and (4) has been studied and homolysis threshold energies determined. Compound (3) particularly... 

Analogously, pyrazolyl-aluminate and -indate ligands have been prepared <75JCS(D)749) and their chelating properties evaluated with cobalt, nickel, copper and zinc. Gallyl derivatives of pyrazoles and indazoles have been extensively studied by Storr and Trotter e.g. 75CJC2944) who determined several X-ray structures of these compounds. These derivatives exist in the solid state as dimers, such as (212) and (288). A NMR study in acetone solution showed the existence of a slow equilibrium between the dimer (212) and two identical tautomers (289) and (290) (Section 4.04.1.5.1) (81JOM(215)157). 

Raney cobalt is generally less effective than Raney nickel, but may be of use when the rupture of other bonds must be avoided. The important use of Raney nickel desulfurization for the structure determination of thiophenes and for the determination of the absolute configuration of optically active thiophene and benzene derivatives has been stressed earlier. 

Luminol derivatives produce emission of light by oxidation with oxygen and hydrogen peroxide under alkaline conditions. By utilizing this reaction, peroxides such as hydrogen peroxide and lipid hydroperoxides can be determined after HPLC separation. Metal ions [e.g., iron(II), cobalt(II), etc.] catalyzing the luminol CL reaction can also be determined. 

To test the validity of the assumption that one cobalt (II) ion is oxidized to cobalt (III) for each ammonia or ethylenediamine molecule formed, a kinetic expression for the total amount of cobalt (II) oxidized was derived. The values of total cobalt (II) oxidized as calculated from this expression were compared with the experimentally determined sums of the amount of ethylenediamine and ammonia formed. 

A urylene derivative of cobalt, [(CpCo)2 (Bu NCONBu1)] (71) has been obtained by the reaction of N-r-butylsulfurimide, (Bu N S, with [CpCo(CO)2]. The reaction has been suggested to proceed via the formation of an intermediate nitrene complex, [CpCo OJNBu1].257,258 The X-ray crystal structural determination has shown the presence of a short Co—Co distance (2.37 A), which is 0.1A smaller than that reported in the related acetylene complex, Co2(CO)6(C2Ph2).258,26 ... 

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