Process for producing 4-halogeno-2-alkoxyimino-3-oxo fatty acid

Claim 1

A one-pot one-step process for producing a 4-halogeno-2-alkoxyimino-3-oxo fatty acid of the formula: ##STR5## wherein X is a halogen atom; R 1 is a hydrogen atom, a linear or branched alkyl group selected from the group consisting of methyl, ethyl, propyl, isopropyl, tert-butyl, octyl and dodecyl, a cyclic alkyl group selected from the group consisting of cyclopropyl, cyclopentyl and cyclohexyl, an aryl group selected from the group consisting of phenyl, tolyl, xylyl and naphthyl or an aralkyl group selected from the group consisting of benzyl and phenethyl; and R 2 is a substituted of unsubstituted, linear or branched alkyl group selected from the group consisting of methyl, methoxymethyl, methylthiomethyl, ethyl, isopropyl, tert-butyl, octyl and dodecyl, a substituted or unsubstituted cyclic alkyl group selected from the group consisting of cyclopropyl, cyclopentyl and 4-methylcyclohexyl, a substituted or unsubstituted aryl group selected from the group consisting of phenyl, 4-chlorophenyl, 2-methoxyphenyl, tolyl, xylyl and napthyl, or a substituted or unsubstituted aralkyl group selected from the group consisting of benzyl, 4-chlorophenyl, 2-methoxybenzyl and phenethyl, consisting essentially of reacting a halogenating agent with a 2-alkoxyimino-3-oxo fatty acid ester of the formula: ##STR6## wherein R 1 and R 2 are as defined above, and R 3 is a tertiary alkyl group selected from the group consisting of tert-butyl, tert-amyl and 1,1-dimethylbutyl, in an ether solvent or a mixed solvent of an ether solvent and an inert organic solvent, and thereby carrying out cleavage of the ester linkage and halogenation of the carbon at the 4-position.