PREPARATION METHOD OF PHENOXYCARBOXYLIC ACID HERBICIDES
Disclosed is a preparation method of phenoxycarboxylic acid herbicides. The preparation method comprises the following steps. S1: mixing an anhydrous phenol and a basic substance with a chloro-substituted carboxylic acid ester and performing a one-pot condensation reaction in an anhydrous system to...
Gespeichert in:
Hauptverfasser: | , , , , |
---|---|
Format: | Patent |
Sprache: | eng |
Schlagworte: | |
Online-Zugang: | Volltext bestellen |
Tags: |
Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
|
Zusammenfassung: | Disclosed is a preparation method of phenoxycarboxylic acid herbicides. The preparation method comprises the following steps. S1: mixing an anhydrous phenol and a basic substance with a chloro-substituted carboxylic acid ester and performing a one-pot condensation reaction in an anhydrous system to obtain a phenoxycarboxylic acid ester. The chloro-substituted carboxylic acid ester is represented by the formula ClR1COOR, in which R1 is a C1-3 alkanediyl or alkylidene group, R is a C1-10 alkyl group or a C3-10 cycloalkyl group; S2: the phenoxycarboxylic acid ester undergoes selective chlorination with a chlorinating agent in the presence of a first catalyst and a second catalyst to obtain a chloro-substituted phenoxycarboxylic acid ester; and S3: the chloro-substituted phenoxycarboxylic acid ester undergoes an acid hydrolysis reaction to obtain a phenoxycarboxylic acid herbicide represented by formula I, in which R3 is H, Cl or CH3. |
---|