反应详情

温度

100 °C

A mixture of 2,3-difluoropyridine (2.00 g, 17.4 mmol), Cs2CO3 (13.59 g, 41.7 mmol) and diethyl malonate (6.68 g, 41.7 mmol) in DMSO (19 mL) was heated at 100° C. for 4.5 h. The mixture was poured onto ice, diluted with EtOAc, and the organic phase was separated, washed sequentially with water and brine, and dried and concentrated. The residue was purified by column chromatography on silica gel (80 g), eluting with EtOAc-hexanes (sequentially 10%, 20% and 30%), to provide diethyl 2-(3-fluoropyridin-2-yl)malonate as a pale colored oil (2.68 g, 60% yield). 1H NMR (400 MHz, chloroform-d) δ 8.42 (dt, J=4.6, 1.3 Hz, 1H), 7.43 (ddd, J=9.4, 8.3, 1.4 Hz, 1H), 7.30 (dt, J=8.5, 4.3 Hz, 1H), 5.09 (d, J=1.1 Hz, 1H), 4.30 (q, J=7.0 Hz, 4H), 1.33-1.26 (m, 6H).

1. additionThe mixture was poured onto ice
2. customthe organic phase was separated
3. washwashed sequentially with water and brine
4. customdried
5. concentrationconcentrated
6. customThe residue was purified by column chromatography on silica gel (80 g)
7. washeluting with EtOAc-hexanes (sequentially 10%, 20% and 30%),