Process for producing 2,3-difluoro-6-nitrophenol
AssigneeHoechst Aktiengesellschaft
InventorsTheodor Papenfuhs, Joachim Hackenbruch, Ralf Pfirmann
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Abstract
According to a process for producing isomer-free 2,3-difluoro-6-nitrophenol, 2,3,4-trifluoronitrobenzene is reacted with an aqueous solution of alkali metal or alkaline earth metal hydroxide in the absence of organic solvent, at temperatures between about 20.degree. C. and 100.degree. C., the pH value of the reaction mixture is set at about 1 to 6 by acid addition, the resulting product is stream distilled and the 2,3-difluoro-6-nitrophenol is isolated after cooling. No organic solvents are used during any of the steps of the process.
Claims9
A process for the preparation of isomerically pure 2,3-difluoro-6-nitrophenol, which comprises reacting 2,3,4-trifluoronitrobenzene with aqueous alkali metal hydroxide solution or alkaline earth metal hydroxide solution or suspension in the absence of organic solvent at temperatures of about 20.degree. C. to about 100.degree. C., adjusting the resulting reaction mixture to a pH of about 1 to about 6 by addition of acid, steam-distilling the resulting product and isolating the 2,3-difluoro-6-nitrophenol from the distillate after cooling, no organic solvent being present in any process step.
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