| 摘要 |
The present invention is directed to a process for the preparation of deactivated anilines, which comprises the step of reacting a compound of formula (I) <IMAGE> (I) with a dialkylamide in the presence of a base at elevated temperature, in which: R1 is chosen from groups whose anions (R1-) constitute leaving groups; R2 and R4, which may be the same or different, are chosen from hydrogen, hydrocarbon chains, halogens and groups which are electron-attracting (EAG); R3 is chosen from hydrocarbon chains, halogens and groups which are electron-attracting, preferably through an inductive effect rather than a mesomeric effect; with the proviso that at least one of the groups R2, R3, and R4 is electron-attracting through an inductive effect. A second embodiment of the present invention is directed to a process for the dealkylation of deactivated anilines which comprises the steps of free radical halogenation of the benzyl carbon followed by hydrogenation. A third embodiment of the present invention is directed to a process for the dealkylation of deactivated anilines which comprises the step of reacting an alkylated aniline with an amine in the presence of a catalytic amount of a pyridine salt. A fourth embodiment of the present invention is direct to intermediates for the preparation of deactivated anilines which have the formula (III) Ar-N(-CH2-xZx-R1')(-CH2-yZy-R2') (III) wherein Z represents a halogen atom; R1' and R2', which may be the same or different, are each a hydrogen atom or an alkyl radical having at most 4 carbons; x and y, which may be the same or different, are each an integer of 0 or 1, with the proviso that x+y is at least equal to 1; and Ar is a deactivated aromatic ring, preferably derived from formula (I) by replacement of R1 with a dialkylamine.
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