反应详情

温度

-10 °C

A mixture of 2.46 g (17.9 mmole) of isonicotinic hydrazide and 50 ml of ethanol was stirred at -10° C. as a solution of 2.52 g (16.6 mmole) of ethyl valerimidate hydrochloride, in 46 ml of ethanol was added dropwise under protection from moisture. The mixture was maintained at -10° C. for three hours and then at 5° C. overnight. The filtered solution was concentrated, and the residue was flash chromatographed on silica gel (elution with 2.5% methanol in CH2Cl2) to provide 2.12 g (50%) of the titled compound as an oil which goes to a waxy solid at 5° C., homogeneous by TLC in 9:1 CH2Cl2 --MeOH; mass spectrum (FAB) m/e 250 (M+1)+. NMR suggested that the product is a mixture of syn and anti-isomers.

1. additionwas added dropwise under protection from moisture
2. customat 5° C.
3. customovernight
4. concentrationThe filtered solution was concentrated
5. customchromatographed on silica gel (elution with 2.5% methanol in CH2Cl2)