反应详情

A stirred solution of diisopropylamine (0.385 mL, 2.70 mmol) in THF (2 mL) at 0° C. was treated slowly with 1.6 M n-butyllithium in hexanes (1.69 mL, 2.70 mmol). The mixture was stirred for 15 min, then was added over 5 min to a stirred solution of 3-methoxy-2-picoline (0.133 g, 1.08 mmol) and diethyl carbonate (0.262 mL, 2.16 mmol) in THF (5 mL) at −78° C. After stirring for 45 min more, the cooling bath was removed and stirring was continued overnight at room temperature. The mixture was treated with saturated aqueous NH4Cl and diluted with EtOAc. The organic phase was separated, washed sequentially with saturated aqueous NaHCO3 and brine, and dried and concentrated. The residue was purified by column chromatography on silica gel (12 g), eluting with 50% EtOAc-hexanes, to provide ethyl 2-(3-methoxypyridin-2-yl)acetate as an oil (0.17 g, 81% yield). Mass spectrum m/z 196 (M+H)+.

1. stirringAfter stirring for 45 min more
2. customthe cooling bath was removed
3. stirringstirring
4. waitwas continued overnight at room temperature
5. additionThe mixture was treated with saturated aqueous NH4Cl
6. additiondiluted with EtOAc
7. customThe organic phase was separated
8. washwashed sequentially with saturated aqueous NaHCO3 and brine
9. customdried
10. concentrationconcentrated
11. customThe residue was purified by column chromatography on silica gel (12 g)
12. washeluting with 50% EtOAc-hexanes