Dienol-benzene rearrangement

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The dienol-benzene rearrangement is a name reaction in organic chemistry and was first published in 1956 by the German chemists Hans Plieninger and Rolf Müller. The reaction describes the synthesis of substituted benzene from substituted dienol.

Overview reaction

4,4-Disubstituted 2,5-Cyclohexadien-1-ol reacts in acidic solution to a 1,2-disubstituted benzene:

Dienol-benzene rearrangement overview reaction

Reaction mechanism

The mechanism is described in the literature:

Dienol-benzene rearrangement mechanism

The 4,4-disubstituted 2,5-cyclohexadien-1-ol 1 is protonated, with the reactive oxonium ion 2 being formed. By splitting off water , the cyclohexadiene cation 3 is formed as a reactive intermediate. The subsequent elimination of a proton leads to the 1,2-disubstituted benzene 4 with aromatization .

Individual evidence

  1. ↑ H. Plieninger, R. Müller (1956): Action of lead tetraacetate on β ‐ ketobutyraldehyde dimethylacetal. Angewandte Chemie , 68, pp. 618-618, doi: 10.1002 / anie.19560681913 .
  2. ↑ VP Vitullo, MJ Cashen, JN Marx, LJ Caudle, JR Fritz (1978): cyclohexadienyl cations. 7. Kinetics and mechanism of the acid-catalyzed dienol-benzene rearrangement. Journal of the American Chemical Society 100 (4), 1205-1210, doi: 10.1021 / ja00472a028 .
  3. ^ MJ Gentles, JB Moss, HL Herzog, EB Hershberg (1958): The Dienol-Benzene Rearrangement. 1 Some Chemistry of 1,4-Androstadiene-3,17-dione. Journal of the American Chemical Society 80 (14), 3702-3705, doi: 10.1021 / ja01547a058 .
  4. ^ Z. Wang: Comprehensive organic name reactions and reagents Volume 1 . John Wiley, Hoboken (NJ) 2009, ISBN 978-0-470-28662-3 , pp. 897-899 .