反应详情

A mixture of ethyl 3-(6-methoxy-3-pyridyl)propionate (32.74 g) and ethyl formate (17.22 g) was added dropwise over 1.5 hours to a stirred suspension of sodium hydride in oil (50%, 9.38 g) in 1,2-dimethoxyethane (50 ml) cooled to -2°, and allowed to stand overnight at room temperature. The mixture was poured on to ice and the mixture was extracted with ether (discarded), and the aqueous phase was adjusted to pH 5 with 2N sulphuric acid. An oil was precipitated and crystallised on standing to give ethyl 2-formyl-3-(6-methoxy-3-pyridyl)propionate (25.9 g, 70%), m.p. 91.5-94°. A sample recrystallised from aqueous ethanol had m.p. 93-94°.

1. temperaturecooled to -2°
2. additionThe mixture was poured on to ice
3. extractionthe mixture was extracted with ether (discarded)
4. customAn oil was precipitated
5. customcrystallised