| 摘要 |
NEW MATERIAL:A compound expressed by formula II. USE:An intermediate for producing compounds, expressed by formula I (R is H, alkyl or phenyl) and having herbicidal efficacy. PREPARATION:One equivalent 1-bromo-2-chloro-4-fluoro-5-nitrogenzene is reacted with 3-30 equivalents, preferably 5-20 equivalents reducing agent, e.g. iron powder, etc., at 60-120 deg.C for 1-20hr to afford the aimed 5-bromo-4-chloro-2- fluoroaniline expressed by formula II. The above-mentioned reaction is carried out in an aqueous solution of acetic acid and, as necessary, in the presence of a co-solvent, e.g. ethyl acetate, etc. The compound expressed by formula II can be reacted with a compound expressed by formula IV to give a compound expressed by formula III, which is then reacted with a compound expressed by formula V to afford the compound, expressed by formula I and having herbicidal efficacy.
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