Cobaltates sepulchrates

The corresponding macrobicyclic cobalt(II) [Co(sep)](ZnCl4) H20 complex was prepared by reduction of the [Co(sep)]Cl3 complex with zinc dust in aqueous HCl [95], A similar procedure was used for the synthesis of the dithionate [Co(sep)](S206) salt in the presence of Li2S206 [99], The optically active R- and S-isomers of cobalt sepulchrate were obtained from the optically active parent A-[Co(en)3]Cl3 and A-[Co(en)3]Cl3 complexes [94-95],... 

Most of the investigations in this field have focused on the use of cobalt sepulchrate and sarcophaginates as electron-transfer sensitizers in photocatalytic cyclic solar energy conversion processes [340, 375-378]. This is mainly due to their specific redox behaviour stipulated by peculiarities of the cobalt ion electronic structure and screening of this ion by an encapsulating ligand. 

Cobalt(II,III) sepulchrates have been used in the chemical education [415] and considerable number of the chemical and physicochemical studies as efficient quencher of the phosphorescence [416] and electronic excited states [417, 418], as a reductant in kinetic studies of redox reactions [419, 420], as a model for study of magnetodynamic [421], solvent [422] and pressure [423] effects on the outer-sphere electron-transfer reactions. Transfer chemical potentials (from solubility measurements) [424], electrochemical reduction potentials [425] and ligand-field parameters [426] for cobalt sepulchrates have been calculated. Solvent effect on Co chemical shift of cobalt(III) ion encapsulated in the sepulchrate cavity [427]... 

These authors have also developed a cell that employs reticulated vitreous carbon as a working electrode they found that such a design allows for much faster electrolysis. Using such a cell, they have studied the couple, a cobalt(III/II) sepulchrate, as well as the Fe—C distance in cytochrome C. For the case of the cobalt sepulchrate, they were able to obtain spectra at five different applied potentials, and as shown in Fig. 20, very well-defined isosbestic points were obtained. 

Cobaltate, tris(l, 2-ethanediamine)-racemization solid state, 466 Cobaltate, tris(oxalato)-racemization solid state, 467 Cobaltates sepulchrates, 22 Cobalt complexes geometric isomerism, 11 hexaammine... 

A quite different, but very important, class of reaction of coordinated ligands is in the synthesis of new coordinated ligands. An excellent example is provided by the synthesis of cobalt sepulchrate (cf. Table 2.5) from [Co(en)3] action of formaldehyde and ammonia in a basic medium... 

Abbreviations. (2 C MV ) N,N -bis(heptyl)-4,4 bipyridinium C-j MV" N-tetradecyl -N -methyl -4,4 -bi pyri di niurn CoCC dicarboxyl -1-7 cobalticinium CoSep cobalt sepulchrate Fd ferredoxin ... 

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