Title:

Favorskii rearrangement of some α-bromo-ketones

Author(s):

Turro, Nicholas J.
Gagosian, Robert B.
Rappe, Christoffer
Knutsson, Leif

Date:

1969

Type:

Articles

Volume:

6

Permanent URL:

http://hdl.handle.net/10022/AC:P:9412

Book/Journal Title:

Journal of the Chemical Society D: Chemical Communications

Abstract:

The base-induced rearrangement of a-halogenoketones to give carboxylic acid derivatives (Favorskii rearrangements1) occurs by at least two mechanisms. The stereochemi~try29~ and structure* of many Favorskii products can be explained in terms of a cyclopropanone intermediate. However, a “benzylic-like” rearrangement appears to operate when the substrate ketone bears no a’-hydrogen,5 when the =’-hydrogen is relatively non-acidic,6 or when steric or strain factors inhibit cyclopropanone formation.’ In addition, the formation of a dipolar intermediate which may precede (or follow) cyclopropanone formation is supported by theoretical considerations,s loss of stereospecificity upon rearrangement in polar solvents,B the formation of a-substitution products* as a side reaction, and the trapping of a possible Favorskii intermediate “dehydrohalogenate” to form a common intermediate leading to the same product.

Subject(s):

Chemistry

DOI:

http://dx.doi.org/10.1039/C29690000270

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