Diastereoisomerism and electrochemical behaviour— an investigation of redox-active cyclophanes

Abstract

The influence of diastereoisomerism on the electrochemical behaviour of the atropisomeric cyclophanes 1a and 1b was found by cyclovoltammetric studies. Compound 1a can be oxidized and reduced reversibly in a two step redox process similar to that of model compound 2. In contrast, 1b shows a different electrochemistry. As a result of a detailed investigation of 1b a complex reaction scheme can be postulated starting with a chemical reaction after the first oxidation step. The special spatial situation in 1b makes possible this EC mechanism reaction, which does not occur in 1a or in unbridged biindolizines.

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