| 摘要 |
The present invention relates to a method for producing N-carboxyalkyl-3-fluoro-4-dialkylaminonilines by reacting an ortho-nitrochlorobenzene of formula (1), wherein X stands for Cl or F, with a secondary amine of formula (2) HNR1R2, wherein R1 and R2 are independently similar or different and stand for an alkyl radical with 1 to 10 carbon atoms or jointly form a ring with 3 to 7 links together with the N atom on which they stand, in the presence of a base in the presence or absence of a solvent agent at -10 to 120 ~C in a first step. In a second step, the 2-chloro-4-dialkylamino-5-fluoronitrobenzene is made to react with hydrogen at 30 to 150 ~C and at 1 to 100 bars in the presence of a base and a noble metal catalyst. In a third step, the 3-fluoro-4-dialkylaminoaniline is extracted from the reaction mixture with an aqueous acid solution in the form of a salt dissolved in water, the aqueous phase is separated and the salt from the 3-fluoro-4-dialkylaminoaniline dissolved in water is made to react in the presence of a basic compound with a chloroformic acid ester of formula (3) CICO2R3, wherein R3 stands for an alkyl radical with 1 to 10 carbon atoms or an aralkyl radical with 7 to 20 carbon atoms, at a temperature of 0 to 100 ~C.
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