ELECTRON-TRANSFER REACTIONS AND ASSOCIATED CONFORMATIONAL CHANGES. STUDIES OF BIANTHRONE REDUCTION VIA HOMOGENEOUS REDOX CATALYSIS.

Article abstract of DOI:10.1021/ja00341a002

The catalyzed reductions of bianthrone (1) and 1,1 prime -dimethylbianthrone have been quantitatively characterized in dimethylformamide solvent. The technique that was employed involves the generation of anion radicals of various quinones at a mercury electrode. As they diffuse near the electrode, these anion radicals can transfer an electron to A form of the bianthrone. At low catalyst concentrations, the rate of reduction of 1 is governed by the forward electron-transfer reaction for each of five quinones. the back reaction was shown to be diffusion controlled. The results were compared with radiolysis studies in a different medium. The present work was the result of interest in the significant role of molecular conformation in the thermodynamics and kinetics of electron-transfer reactions. Refs.