Fast Esterification of Fatty Acids with Alkyl Chloroformates Optimization and Application in Gas Chromatography

Alkyl chloroformates with methyl, ethyl, and 2-chloroethyl substituents can instantaneously esterify fatty acids under proper reaction conditions. Apart from the formation of the corresponding alkyl esters, even the alkoxycarbonyl esters can be prepared. These derivatives are useful for the analysis of short-chain fatty acids. As alkoxycarbonyl ester, even acetic acid can already be separated from the solvent peak. The reaction conditions were examined, and the influence of solvent polarity and reagent concentration on the conversion was studied. Quantitative conversion of acids to their esters was achieved in non-aqueous solutions, but even in the presence of water the yields were acceptable.