Water → HCID 22673287, compound

45.1 g of (±)-2-azabicyclo[2.2.1]hept-5-en-3-one were dissolved in acetonitrile (310 ml) and pyridine (39 ml) under nitrogen. At 10° C., 54.1 g of isobutyryl chloride were added dropwise over the course of 1 h. The reaction was then stirred at room temperature for 5 h. 140 ml of water were added to the mixture, and the acetonitrile was evaporated off in vacuo. The aqueous phase was extracted with 4×120 ml of ethyl acetate. The combined organic phases were washed with 1N HCl (50 ml), saturated NaHCO3 (50 ml) and NaCl (50 ml) solutions, dried with sodium sulphate and completely evaporated. The residue was boiled under reflux in n-hexane (240 ml) with active charcoal. After filtration of the active charcoal, the filtrate was cooled to 0° C. and the title compound was filtered. 54.5 g of product were obtained. The yield was 76%.

1. customthe acetonitrile was evaporated off in vacuo
2. extractionThe aqueous phase was extracted with 4×120 ml of ethyl acetate
3. washThe combined organic phases were washed with 1N HCl (50 ml), saturated NaHCO3 (50 ml) and NaCl (50 ml) solutions
4. dry with materialdried with sodium sulphate
5. customcompletely evaporated
6. temperatureunder reflux in n-hexane (240 ml) with active charcoal
7. filtrationAfter filtration of the active charcoal
8. temperaturethe filtrate was cooled to 0° C.
9. filtrationthe title compound was filtered

ORD record

ord-c7239b52c63942c08039a31cdc0ccb0c

Source dataset

uspto-grants-2004_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06787347B2