The present review surveys some of the recent developments in the methodology for the transposition of carbonyl group including related hydroxy transposition.
The chapter of “1, 2-Transposition” describes various methods which are classified according to the methods for α-functionalization of carbonyls. The methods concerned include benzylidenation, acetoxylation, bromination oximination, nitration, sulfenylation, and hydroboration.
The chapter of “1, 3-Transposition” deals mainly with the 1, 3-transposition in α, β-unsaturated carbonyl systems. Among the methods described here are included ones which are based on the Wharton reaction, the oxidative rearrangement of allylic alcohols, the 1, 3-hydroxy transposition, the interconversion of sulfoxides and sulfenates via the [2, 3] sigmatropy, the [3, 3] sigmatropy of allylic thion-esters, and oxidative cyclization of enon-oximes to isoxazoles.
Finally, the chapter of “1, n (n>3) -Transposition” describes the Willgerodt-Kindler methods and points out some possibilities of 1, 4-transposition
via the Barton reaction and the cyclopropane ring-opening and of 1, n (n>4) -transposition based on the microbial transformations.
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