Patent ID: 7034156

Claim:
A process for preparing a compound of formula (I) in which is hydrogen, cyano, nitro, or halogen, R 2 is cyano, nitro, halogen, or optionally substituted alkyl or alkoxy, R 3 is hydrogen, hydroxyl, mercapto, amino, hydroxyamino, hydrazino, halogen, or one of the radicals —R 6 , -Q-R 6 , —NH—R 6 , —NH—O—R 6 , —NH—SO 2 —R 6 , —N(SO 2 —R 6 ) 2 , —CQ 1 -R 6 , —CQ 1 -Q 2 -R 6 , —CQ 1 -NH—R 6 , -Q 2 -CQ 1 -R 6 , —NH—CQ 1 -R 6 , —N(SO 2 —R 6 )(CQ 1 -R 6 ), -Q 2 -CQ 1 -Q 2 -R 6 , —NH—CQ 1 -Q 2 -R 6 , or -Q 2 -CQ 1 -NH—R 6 , where Q is O, S, SO, or SO 2 , Q 1 and Q 2 are each independently oxygen or sulphur, and R 6 is optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkylalkyl, aryl, arylalkyl, heterocyclyl, or heterocyclylalkyl, R 4 is hydrogen, halogen, or optionally substituted alkyl, and R 5 is fluorine- and/or chlorine-substituted alkyl, comprising reacting a compound of formula (II) in which R 1 , R 2 , R 3 , R 4 , and R 5 are each as defined for formula (I), with a dehydrating agent at temperatures between −30° C. and +180° C.