反应详情

A solution of methyl N-(2-fluoro-4-chloro-5-isobutyloxycarbonyloxyphenyl)carbamate (5.37 g, 16.8 mmol) prepared by the process as shown in Reference Example 3, 3-methylcyclopentyl p-toluenesulfonate (5.0 g, 20.2 mmol) and potassium carbonate (2.32 g, 16.8 mmol) in methanol (50 ml) was stirred for 5 hours under refluxing. After completion of the reaction, the reaction mixture was poured into 1N hydrochloric acid (100 ml), and the mixture was extracted with ethyl acetate (50 ml×3 times). The organic layer was dried, and the solvent was distilled off under reduced pressure to obtain methyl N-{2-fluoro-4-chloro-5-(3-methylcyclopentyl)oxyphenyl}carbamate as grey white crystals (3.81 g, 12.6 mmol, 75.2% yield). 1H-NMR Spectrum (CDCl3, TMS, ppm): δ1.02 and 1.08 (total 3H, d, J=6.0 Hz), 1.25-2.40 (7H, m), 3.77 (3H, s), 4.75 (1H, m), 6.68 (1H, br, s) 7.05 (1H, d, JHF =10.5 Hz), 7.75 (1H, d, JHF =7.5 Hz).

1. temperatureunder refluxing
2. customAfter completion of the reaction
3. extractionthe mixture was extracted with ethyl acetate (50 ml×3 times)
4. customThe organic layer was dried
5. distillationthe solvent was distilled off under reduced pressure