Electrochemical oxidation and reduction of complexes using inert electrodes

1 Electrochemical oxidation and reduction of complexes using inert electrodes 

The electrochemical generation and reactions of [PtL2l equivalents and related low valent, formally unsaturated intermediates, has been 

The cathodic reduction of [Fe(acac 3] in methanol in the presence of the strong 71-acceptors, PPhs and 1,3-butadiene, yields [Fe(l,3-butadiene)2(PPh3)].23 The electrochemical reduction of the d -complexes, [M(R)Cl2(CO)(PPh3)2l (M = Rh, Ir R = alkyl), leads to the elimination of two chloride ions and the formation of the d -complexes, [M(R)(CO)(PPh3)2], which are more difficult to prepare by routine chemical methods.24 

Controlled potential electrolysis of the neutral rhodium(l) acetylide (alkynyl) complex, [Rh(CCR) N(C2H4PPh2)3 ] (R = Ph, C02Et), in THF in the presence of [(n-Bu)4N][C104] at-0.2 V (vs. SCE) yields the rhodium(II) complex, [Rh(CCR)(N(C2H4PPh2)3)][C104], in good yield.28 

Among the most familiar electrosynthetic reactions involving the oxidation of a metal center in a coordination compound is the conversion of alkali metal hexacyanoferrates(II) to the corresponding hexacyanoferrates(III). When the electrolysis is carried out in a divided cell equipped with diaphragm, the electrooxidation is practically quantitative. In a review of studies of the oxidation of [Fe(CN)6] it was noted s that the rate of oxidation of the hexacyanoferrate(II) anion depends on a large number of factors, including the current density, the concentration of the complex in solution, the electrode material, the temperature, and the pH of the solution. 

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