Electrochemical reduction of some pyridinium and sulfonium ylides

✍ Scribed by George Kokkinidis; Evangelia Hatzigrigoriou; Dimitra Sazou; Anastasios Varvoglis

• Publisher: Elsevier Science
• Year: 1991
• Tongue: English
• Weight: 508 KB
• Volume: 36
• Category: Article
• ISSN: 0013-4686
• DOI: 10.1016/0013-4686(91)85186-b

✦ Synopsis

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electrochemical reduction of some pyridinium and sulfonium dicyanomethylides ss well as pyridinium ylides coming from an amidic precursor on mercury cathodes has been investigated by employing polarography, cyclic voltsrnmetry and controlled potential electrolysis. In neutral solutions, pyridinium ylides are reduced in one single step. The primary radical anion formed after the first electron uptake either dimerizes or undergoes further reduction through protonation and cleavage of the C-N bond after the second electron uptake. In acid solutions, protonation in the bulk solution is followed by electroreduction exclusively through cleavage of the C-N bond. Electroreduction of sulfonium dicyanomethylides leads also to the cleavage of the sulfur-carbon bond by means of a two-electron reaction.