METHOD FOR PREPARING DERIVATIVES OF 1-PHENYLPYRAZOLINE-3-CARBOXYLIC ACID Russian patent published in 2004 - IPC

FIELD: organic chemistry, chemical technology, agriculture.

SUBSTANCE: invention describes a method for preparing derivatives of 1-phenylpyrazoline-3-carboxylic acid of the general formula (III) by base-catalyzed reaction of hydrazones of the general formula (I) with olefins of the general formula (II). Compounds of formulas (I), (II) and (III) are given in the invention claim. Reaction is carried out in the presence of triethylamine wherein Ph means possibly substituted phenyl; R¹ means hydrogen atom or alkyl; R² and R³ mean independently of one another hydrogen, halogen atom, cyano-group, possibly substituted organic residue; or R² and R³ in common with carbon atom bound with them form saturated 5- or 6-membered cycle; X means amino-group, hydroxyl, alkoxyl, cycloalkoxyl, alkylamino-group, dialkylamino-group, alkyloxyalkyloxy-group, trialkylsilyloxy-group or trialkylsilylmethyloxy-group; Y means chlorine or bromine atom. Process is carried out in two-phase system consisting of organic and an aqueous phase in using triethylamine or, if necessary, another base. Derivatives of the formula (III) are used as antidotes, i. e. as agents that protect useful plants in agricultural and forestry cultures against unfavorable injures caused by herbicides.

EFFECT: improved preparing method, valuable agricultural properties of compounds.

11 cl, 1 tbl, 1 ex