Patent ID: 6846952

Claim:
A process for producing 4-bromo-2-oxyimino butyric acid, predominantly as the (Z)-isomer of formula (I), wherein R is is selected from the group consisting of hydrogen; a linear or branched C 1-4 alkyl group; a linear or branched C 1-4 alkyl group substituted by a carboxylic acid or an aryl group; a substituted or unsubstituted cyclic alkyl group of 3-6 carbon atoms and a substituted or unsubstituted aryl group which comprises reacting bromine with a 2-(oxyimino)-3-oxo butyric acid derivative of formula (II) wherein R is as defined above and R 1 is a tert-butyl group in presence of an organic solvent and in presence of a C 1-4 alcohol and acetyl bromide at a temperature ranging from about −15° C. to about +15° C.