| 摘要 |
The present invention relates to a process for the preparation of N-carboxyalkyl-3-fluoro-4-dialkylaminoanilines, which comprises reacting, in a first step, an orthonitrochlorobenzene of the formula (1) in which X is Cl or F, with a secondary amine of the formula (2) HNR1R2, in which R1 and R2, independently of one another, are identical or different and are an alkyl radical having from 1 to 10 carbon atoms or, together with the N atom to which they are bonded, form a ring having from 3 to 7 members, in the presence of a base in the presence or absence of a solvent at from -10 to 120 DEG C., reacting, in a second step, the 2-chloro-4-dialkylamino-5-fluoronitrobenzene with hydrogen at from 30 to 150 DEG C. and from 1 to 100 bar in the presence of a base and a noble-metal catalyst and, in a third step, extracting the 3-fluoro-4-dialkylaminoaniline from the reaction mixture using an aqueous solution of an acid as a salt dissolved in water, removing the aqueous phase and reacting the 3-fluoro-4-dialkylaminoaniline salt, dissolved in water, with a chloroformate of the formula (3) ClCO2R3, in which R3 is an alkyl radical having from 1 to 10 carbon atoms or an aralkyl radical having from 7 to 20 carbon atoms, at from 0 to 100 DEG C. in the presence of a basic compound. |
