| CPC C07C 209/84 (2013.01) [C07C 209/74 (2013.01)] | 7 Claims |
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1. A method for preparing a trifluoromethyl aromatic compound, comprising:
mixing a trichloromethyl aromatic compound with an organic alkali hydrofluoride to obtain a mixture, and subjecting the mixture to fluorination to obtain a reaction solution, wherein a molar ratio of the trichloromethyl aromatic compound to the organic alkali hydrofluoride is in a range of 1: (1-3);
subjecting the reaction solution to solid-liquid separation to obtain an organic alkali hydrochloride wet product and a filtrate, drying the organic alkali hydrochloride wet product, and condensing and recycling a gas generated during the drying to obtain a condensed product; and
purifying the filtrate and the condensed product by rectification to obtain the trifluoromethyl aromatic compound;
wherein the trichloromethyl aromatic compound comprises one selected from the group consisting of a trichloromethyl benzene compound and a trichloromethyl pyridine compound: the trichloromethyl benzene compound has a structure as shown in Formula I; and the trichloromethyl pyridine compound has a structure as shown in Formula II;
![]() wherein
in Formula I: R1 is halogen and R2 is —NO2; and in Formula II: R is halogen; and
under the condition that a pot residue obtained from the rectification comprises one or more selected from the group consisting of the trichloromethyl aromatic compound, a monofluoro substitute and a difluoro substitute thereof, the method further comprising: returning the pot residue obtained from the rectification to the fluorination for reuse.
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