反应详情

12.5 ml (0.17 mol) of thionyl chloride are added dropwise with ice-cooling to a suspension of 29.25 g (0.15 mol) of 6-butyl-2-oxo-1,2-dihydro-isonicotinic acid in 200 ml of methanol and the mixture is stirred overnight at room temperature. It is concentrated to dryness and the residue is chromatographed on 450 g of silica gel (230-400 mesh) using dichloromethane→dichloromethane/methanol 10:1. 29.6 g (94%) of colourless crystals m.p.: 106° C. crystallise from dichloromethane, ether and petroleum ether.

1. concentrationIt is concentrated to dryness
2. customthe residue is chromatographed on 450 g of silica gel (230-400 mesh)
3. custom29.6 g (94%) of colourless crystals m.p.: 106° C. crystallise from dichloromethane, ether and petroleum ether