Patent ID: 6861522

Claim:
A process for the preparation of a compound of the formula and optionally its E/Z-isomers, E/Z-isomer mixtures and/or tautomers, in each case in free form or in salt form, in which Q is CH or N; Y is NO 2 or CN; Z is CHR 3 , O, NR 3 or S; R 1 and R 2 are either, independently of one another, hydrogen, unsubstituted or R 4 -substituted C 1 -C 8 alkyl, or together are an alkylene bridge having two or three carbon atoms which optionally comprises a heteroatom chosen from the group consisting of NR 5 , O and S, R 3 is H or unsubstituted or R 4 -substituted C 1 -C 12 alkyl, R 4 is unsubstituted or substituted aryl or heteroaryl, and R 4 is H or C 1 -C 12 alkyl; in which a) a compound of the formula which is known or can be prepared by known methods, and in which X is a leaving group, is reacted with a halogenating agent to give a compound of the formula In which W is a halogen atom, or optionally a tautomer, in each case in free form or in salt form; and in which the work-up of the compound of formula (III) involves an extraction of the compound of formula (III) with hydrochloric acid of concentration between 10 and 50% by weight; and b) the resulting compound of the formula (III) is reacted with a compound of the formula in which R 1, R 2, Y, Z and Q have the meanings given above for the compound of the formula (I); wherein the preparation of the compound of the formula (III) according to process stage a) involves a purification step in which the crude product which has formed is treated with water in the acidic pH range.