Nicotinamide electroreduction

Rhodium and ruthenium complexes have also been studied as effective catalysts. Rh(diphos)2Cl [diphos = l,2-bis(diphenyl-phosphino)ethane] catalyzed the electroreduction of C02 in acetonitrile solution.146 Formate was produced at current efficiencies of ca. 20-40% in dry acetonitrile at ca. -1.5 V (versus Ag wire). It was suggested that acetonitrile itself was the source of the hydrogen atom and that formation of the hydride HRh(diphos)2 as an active intermediate was involved. Rh(bpy)3Cl3, which had been used as a catalyst for the two-electron reduction of NAD+ (nicotinamide adenine dinucleotide) to NADH by Wienkamp and Steckhan,147 has also acted as a catalyst for C02 reduction in aqueous solutions (0.1 M TEAP) at -1.1 V versus SCE using Hg, Pb, In, graphite, and n-Ti02 electrodes.148 Formate was the main... 

Poly(toluidine blue) electrode was used as a nitrite amperometric sensor [235]. Because this compound also exhibits good electrocatalytic activity toward NO, such a sensor was also developed [170]. The product of the electroreduction of NAD was identified as enzymatically active NADH at poly(neutral red) electrodes, which is a very important recognition regarding the application of PNR electrodes in the study, and the electrochemical regeneration of nicotinamide adenine dinucleotide [236]. 

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