Payne rearrangement

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The Payne rearrangement is a name reaction in organic chemistry . It is the base-catalyzed, stereospecific rearrangement of 2,3- epoxy alcohols into isomeric epoxy alcohols . An intramolecular nucleophilic substitution reaction takes place as an (S N 2) reaction.

The reaction was first reported in 1931 by, among others, the American chemist Elmer Peter Kohler (1865–1938). The mechanism was then proposed by Angyal and Gilham in 1957. It was finally named after George B. Payne, who researched it more closely.

Overview reaction

In the case of the 2,3-epoxy alcohol, the epoxy group rearranges and the isomeric epoxy alcohol is obtained.

Overview reaction of the Payne rearrangement

The reaction is reversible and the equilibrium is on the side of the more substituted epoxy isomer.

Reaction mechanism

The following mechanism is described in the literature:

Reaction mechanism of the Payne rearrangement

The hydroxide ion causes deprotonation of the 2,3-epoxy alcohol with elimination of water. The anion 1 is obtained as an intermediate . In the next step, an intramolecular nucleophilic substitution of the second order (S N 2) takes place. This proceeds with a configuration reversal and intermediate product 2 is obtained. The isomeric epoxy alcohol 3 is obtained as the product through the subsequent protonation .

Individual evidence

  1. ↑ a b c Zerong Wang: Comprehensive Organic Name Reactions and Reagents , Wiley, 2010, ISBN 9780470638859 , pp. 2139-2141, doi: 10.1002 / 9780470638859 .
  2. ↑ EP Kohler, NK Richtmeyer and WF Hester: THE ACTION OF ORGANIC MAGNESIUM COMPOUNDS ON ALPHA OXIDO KETONES AND ESTERS In: Journal of the American Chemical Society 53, 1931, pp 205-221, doi: 10.1021 / ja01352a028 .
  3. ^ SJ Angyal and PT Gilham: Cyclitols. Part VII. Anhydroinositols and the epoxide migration. In: Journal of the Chemical Society , 1957, pp. 3691-3699, doi: 10.1039 / JR9570003691 .
  4. ↑ GB Payne: Epoxide Migrations with α, β-Epoxy Alcohols In: The Journal of Organic Chemistry 27, 1962, pp. 3819-3822, doi: 10.1021 / jo01058a015 .
  5. ↑ RM Hanson: Epoxide Migration (Payne Rearrangement) and Related Reactions In: Organic Reactions 60, 2002, p. 1, doi: 10.1002 / 0471264180.or060.01 .