反应详情

温度

80 °C

Phosporous oxychloride (4.76 ml, 51 mmol) was added within 10 minutes to an ice cold solution of (E)-2-cyano-oct-2-enoic acid methyl ester (4.65 g, 26 mmol) in DMF (12 ml) under an argon atmosphere. The reaction mixture was stirred for 14 h at 80° C. and poured onto ice water. After 3 h the mixture was extracted two times with dichloromethane, the combined extracts were washed with ice water and dried over sodium sulfate. Removal of the solvent under reduced pressure left a brown oil which was purified by column chromatography (silica gel, isopropyl acetate/heptane) to give 5-butyl-2-chloro-nicotinic acid methyl ester (1.01 g, 4.4 mmol; 17%) as yellow oil. MS: m/e=227.0 [M+H+].

1. additionpoured onto ice water
2. extractionAfter 3 h the mixture was extracted two times with dichloromethane
3. washthe combined extracts were washed with ice water
4. dry with materialdried over sodium sulfate
5. customRemoval of the solvent under reduced pressure
6. waitleft a brown oil which
7. customwas purified by column chromatography (silica gel, isopropyl acetate/heptane)