| 摘要 |
The invention provides a process for separating a para- fluoro aniline from a corresponding para-unsubstituted aniline characterised by dissolving a starting mixture of a para- fluoro aniline of general formula I <CHEM> wherein one of R<1>, R<2>, R<3> and R<4> is a hydrogen atom, a halogen atom, a C1-3 alkyl group or a CF3 group, the others being independently selected from hydrogen atoms, halogen atoms and C1-3 alkyl groups, and R<5> and R<6> are selected from hydrogen and alkyl groups, and a corresponding para-unsubstituted aniline of general formula II <CHEM> wherein R<1>, R<2>, R<3>, R<4>, R<5> and R<6> are the same as in formula I in an aqueous solution of a non-oxidising acid, and cooling the solution to allow a mixture of salts of the anilines of formulae I and II having a highest mol percentage of the aniline of formula I than in the starting mixture to crystallise out.
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