Electrochemical reduction of the dichloro(3,6-diazaoctane-1,8-diamine)rhodium(III) cation, cis-α-[Rh(trien)Cl2]

Abstract

The electrochemical reduction of cis-α-[Rh(trien)Cl₂]⁺[trien = triethylenetetramine (3,6-diazaoctane-1,8-diamine)] has been studied using polarography and controlled potential electrolysis. The polarographic half-wave potential was found to depend on the pH above ca. 6.0; this was attributed to the catalysed hydrolysis of the starting complex to the corresponding chloroaqua or chlorohydroxy ion by rhodium(I), which was the initial product of the electrochemical reduction. Below pH ca. 6.0, no such conversion occurs because the rhodium(I) is removed rapidly from the system by reaction with H₃O⁺ to form a rhodium(III) hydride.