反应详情

3-(3,3-Dimethyl-1-oxo-isochroman-4-yl)-3H-imidazole-4-carbaldehyde (0.100 g, 0.363 mmol) (Example 9a) in ethanol (3 mL) is added to NaHCO3 (0.246 g, 2.901 mmol) and hydroxylamine hydrochloride (0.208 g, 2.901 mmol) in water (1 mL). After 1 hr, water is added and the mixture is extracted three times with dichloromethane. The combined organic phase is dried over magnesium sulfate and filtered through a cotton plug. Concentration in vacuo gives a residue, which is purified by silica gel flash chromatography (elution with dichloromethane-methanol, 49:1), resulting in the separation of the two isomers. Each isomer is obtained as a white solid.

1. extractionthe mixture is extracted three times with dichloromethane
2. dry with materialThe combined organic phase is dried over magnesium sulfate
3. filtrationfiltered through a cotton plug
4. concentrationConcentration in vacuo
5. customgives a residue, which
6. customis purified by silica gel flash chromatography (elution with dichloromethane-methanol, 49:1)
7. customresulting in the separation of the two isomers
8. customEach isomer is obtained as a white solid