反应详情

The product of Step A (1.80 g, 7.94 mmol) was added to a suspension of KOtBu (980 mg, 8.73 mmol) in anhydrous DMF (15 mL) at 0° C. After stirring for two minutes, a solution of methyl 4-(1-bromobutyl)benzoate in DMF (5 mL) was added dropwise. The mixture was allowed to warm to room temperature. After stirring for 20 minutes, water was added then the solution was extracted with CH2Cl2 (2×100 mL). The combined organic layers were washed with saturated NH4Cl (aq) (20 mL) then saturated NaCl (aq) (20 mL), dried over Na2SO4, filtered, then concentrated. The residue was purified by silica gel chromatography eluting with 2% EtOAc/petroleum ether to afford the title compound: 1H NMR (CD3OD, 300 MHz) δ 7.98-8.02 (m, 2H), 7.77-7.81 (m, 2H), 7.38-7.44 (m, 2H), 7.09-7.13 (m, 2H), 3.91 (s, 3H), 3.79-3.81 (m, 1H), 3.34-3.40 (m, 1H), 1.20-1.30 (m, 2H), 1.03 (s, 9H), 0.91-1.02 (m, 2H), 0.68 (t, J=7.4 Hz, 3H).

1. stirringAfter stirring for 20 minutes
2. extractionthe solution was extracted with CH2Cl2 (2×100 mL)
3. washThe combined organic layers were washed with saturated NH4Cl (aq) (20 mL)
4. dry with materialsaturated NaCl (aq) (20 mL), dried over Na2SO4
5. filtrationfiltered
6. concentrationconcentrated
7. customThe residue was purified by silica gel chromatography
8. washeluting with 2% EtOAc/petroleum ether