反应详情

温度

0 °C

N-Iodosuccinimide (5.25 g, 23.3 mmol) was added portionwise to a solution of methyl 2-cyclobutyl-4-methylbenzoate (219.2, 4.77 g, 23.3 mmol) in concentrated sulfuric acid (100 ml) at 0° C. The mixture turned very thick after it was stirred at 0° C. for 30 min and at RT for 2 hours. The mixture was cooled to 0° C. again and MeOH (100 ml) was added. The mixture was heated at 60° C. for 2 hours. The methanol was removed under reduced pressure and the residue was poured into ice water (200 ml). The mixture was extracted with EtOAc (2×). The combined organic layers were washed with brine, then aq. 1N NaHCO3, dried (Na2SO4), and concentrated. The residue was purified using column (silica gel) chromatography (hexanes:EtOAc 30:1 to 20:1). Yield: 5.0 g, clear oil, 65%. 1H NMR (400 MHz, Chloroform-d) δ 8.19 (s, 1H), 7.24 (s, 1H), 4.17-4.04 (m, 1H), 3.86 (s, 3H), 2.48-2.44 (s, 3H), 2.40-2.28 (m, 2H), 2.13-1.92 (m, 3H), 1.85-1.75 (m, 1H).

1. temperatureThe mixture was cooled to 0° C. again
2. temperatureThe mixture was heated at 60° C. for 2 hours
3. customThe methanol was removed under reduced pressure
4. additionthe residue was poured into ice water (200 ml)
5. extractionThe mixture was extracted with EtOAc (2×)
6. washThe combined organic layers were washed with brine
7. dry with materialaq. 1N NaHCO3, dried (Na2SO4)
8. concentrationconcentrated
9. customThe residue was purified