Patent ID: 7019162

Claim:
A process for producing a 2-fluoro-3-oxoalkylcarboxylic acid ester represented by the following general formula (2): wherein R 1 represents alkyl or alkenyl group and R 2 represents a protective group of carboxyl group, which consists of fluorinating with fluorine gas a 3-oxoalkylcarboxylic acid ester represented by the following general formula (1): wherein R 1 and R 2 are the same as defined above, wherein a concentration of the 3-oxoalkylcarboxylic acid ester in a reaction mixture for fluorination is maintained at 3 wt % or higher, while formation of 2,5-difluoro-3-oxoalkylcarboxylic acid ester is controlled and 2,4-difluoro-3-oxoalkylcarboxylic acid ester and 2,2,4-trifluoro-3-oxyalkylcarboxylic acid ester are selectively removed.