Hydrochloric Acid → 2-Fluoro-4-chloro-5-cyclohexyloxyaniline

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Reaction Conditions

Reaction Steps

Methyl N-(2-fluoro-4-chloro-5-hydroxyphenyl)carbamate (1.00 g, 4.56 mmol) synthesized by the process described in Reference Example 3, cyclohexyl p-toluenesulfonate (1.20 g, 4.73 mmol), potassium carbonate (635 mg, 4.95 mmol), a catalytic amount of potassium iodide and N,N-dimethylformamide (20 ml) as a solvent were charged into a 100 cc round-bottom flask, and stirred on an oil bath at 80° C. After completion of the reaction, the reaction solution was cooled to room temperature, 1N hydrochloric acid (100 ml) was added thereto, and the mixture was extracted with ethyl acetate (20 ml×3). The organic layers were combined, washed with water and a saturated aqueous solution of sodium chloride and dried over anhydrous magnesium sulfate. The drying agent was removed by filtration, the solvent was distilled off under reduced pressure to obtain a crude product (875 mg). The product was isolated and purified by silica gel column chromatography (development solvent: hexane/ethyl acetate=9/1) to obtain methyl N-(2-fluoro-4-chloro-5-cyclohexyloxyphenyl)carbamate (12 mg, 0.46 m 8.1% yield), 2-fluoro-4-chloro-5-cyclohexyloxyaniline (213 mg, 0.87 mmol, 19% yield) and the unreacted starting material, methyl N-(2-fluoro-4-chloro-5-hydroxyphenyl)-carbamate (540 mg, 2.48 mmol, 54% recovery ratio). [Methyl N-(2-fluoro-4-chloro-5-cyclohexyloxyphenyl)carbamate]

Provenance & Evidence