Utilization of Acyloins. I.

Abstract

The synthesis and reduction of acyloins, both symmetrical and mixed, were studied. A series of C8C36 symmetrical and mixed acyloins could be obtained by the condensation of methyl esters of fatty acids under presence of metallic sodium dispersion in inert solvent such as xylene. From mass spectra of the mixed acyloins obtained above, it was found that the reaction of different kinds of fatty esters usually gave the mixed acyloin, in which the long chain had a carbonyl radical and the short chain contained a hydroxyl group. For example methyl butyrate and methyl caprinate reacted as follows : These acyloins were reduced to the corresponding unsymmetrical ketone by the Clemmensen method. In this reduction the hydroxyl group changed into methylene group leaving the carbonyl group unreacted as shown in the following example : The yields were 94%. The Clemmensen reduction of long chain ketone didn't give the corresponding hydrocarbons, while Wolff-Kishner reduction gave hydrocarbon in rather good yields.