反应详情

Sulfuric acid (1.88 mL, 22.3 mmol) was added to a solution of the benzoic acid from step B (5.3 g, 17.1 mmol) in methanol (34 mL) at room temperature. The resulting mixture was stirred at reflux overnight. The mixture was allowed to cool to room temperature then concentrated. The resulting residue was dissolved in EtOAc then washed with saturated NaHCO3 (aq), water, then saturated NaCl (aq). The organics were dried over MgSO4, filtered, then concentrated. The resulting residue was purified by silica gel chromatography eluting with 0-10% MeOH/CH2Cl2 to afford the title compound as a white solid. 1H NMR (600 MHz, CDCl3): δ 7.78 (dd, J=5.4, 1.0 Hz, 1H); 3.93 (s, 3H); 0.43 (s, 9H).

1. temperatureat reflux overnight
2. concentrationthen concentrated
3. dissolutionThe resulting residue was dissolved in EtOAc
4. washthen washed with saturated NaHCO3 (aq), water
5. dry with materialThe organics were dried over MgSO4
6. filtrationfiltered
7. concentrationconcentrated
8. customThe resulting residue was purified by silica gel chromatography
9. washeluting with 0-10% MeOH/CH2Cl2