Kolbe electrolysis

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Kolbe electrolysis or Kolbe reaction is an organic reaction named after Adolph Wilhelm Hermann Kolbe.^[1] ^[2] The Kolbe reaction is formally a decarboxylative dimerisation and proceeds by a radical reaction mechanism.^[3] Generally, the reaction can be observed as:

R₁COO⁻ + R₂COO⁻ → R₁-R₂ + 2 CO₂

If R₁, R₂ are different, then alkanes R₁-R₁ and R₂-R₂ are also formed.

As an example, electrolysis of acetic acid yields ethane and carbon dioxide:

CH₃COOH → CH₃COO⁻ → CH₃COO· → CH₃· + CO₂

2CH₃· → CH₃CH₃

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

[edit] See also

^ Hermann Kolbe (1848). "Zersetzung der Valeriansäure durch den elektrischen Strom". Annalen der Chemie und Pharmacie 64 (3): 339–341. doi:10.1002/jlac.18480640346.
^ Hermann Kolbe (1849). "Untersuchungen über die Elektrolyse organischer Verbindungen". Annalen der Chemie und Pharmacie 69 (3): 257–372. doi:10.1002/jlac.18490690302.
^ A. K. Vijh, B. E. Conway (1967). "Electrode Kinetic Aspects of the Kolbe Reaction". Chem. Rev. 67 (6): 623–664. doi:10.1021/cr60250a003.
^ W. H. Sharkey and C. M. Langkammerer (1973), "2,7-Dimethyl-2,7-dinitrooctane", Org. Synth., http://www.orgsyn.org/orgsyn/orgsyn/prepContent.asp?prep=cv5p0445 ; Coll. Vol. 5: 445