Kolbe electrolysis

The Kolbe electrolysis or Kolbe reaction is an organic reaction named after Hermann Kolbe. The Kolbe reaction is formally a decarboxylative dimerisation of two carboxylic acids (or carboxylate ions) The overall general reaction is:

If a mixture of two different carboxylates are used, all combinations of them are generally seen as the organic product structures:

The reaction mechanism involves a two-stage radical process: electrochemical decarboxylation gives a radical intermediate, then two such intermediates combine to form a covalent bond. As an example, electrolysis of acetic acid yields ethane and carbon dioxide:

Another example is the synthesis of 2,7-dimethyl-2,7-dinitrooctane from 4-methyl-4-nitrovaleric acid:

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