反应详情

温度

60 °C

To a solution of (3S)-2-(tert-butoxycarbonyl)-2-azabicyclo[2.2.2]octane-3-carboxylic acid (0.511 g) and triethylamine (0.348 mL) in tetrahydrofuran (5 mL) was added isobutyl chloroformate (0.26 mL) while stirring under ice-cooling. After stirring at room temperature for 30 min, a solution of 3-amino-5-bromothiophene-2-carboxamide (0.221 g) produced in Example 1, step D, in tetrahydrofuran (1 mL) was added. The reaction system was stirred with heating at 60° C. for 4 days. Water was poured into the reaction system, and the mixture was extracted with ethyl acetate, and dried over anhydrous sodium sulfate. Insoluble material was removed by filtration, and the filtrate was concentrated under reduced pressure. 2M Aqueous sodium hydroxide solution (3.0 mL) and 1,2-dimethoxyethane (6.0 mL) were added to the residue, and the mixture was stirred with heating in a microwave reactor at 150° C. for 1 hr. Insoluble material was removed by filtration, and the mixture was extracted with ethyl acetate, and dried over anhydrous sodium sulfate. Insoluble material was removed by filtration, and the filtrate was concentrated under reduced pressure. The residue was purified by basic silica gel column chromatography (ethyl acetate/hexane) to give the title compound (193 mg) as a colorless solid. The optical purity was 70% ee. The analysis was performed by high performance liquid chromatography (column: CHIRALPAK AD-H (4.6 mm i.d.×250 mm L, manufactured by DAICEL CHEMICAL INDUSTRIES, LTD.), mobile phase: hexane/ethanol (800/200), flow rate: 1.0 mL/min, column temperature: 30° C., detection 220 nm).

1. temperaturecooling
2. stirringAfter stirring at room temperature for 30 min
3. stirringThe reaction system was stirred
4. extractionthe mixture was extracted with ethyl acetate
5. dry with materialdried over anhydrous sodium sulfate
6. customInsoluble material was removed by filtration
7. concentrationthe filtrate was concentrated under reduced pressure
8. addition2M Aqueous sodium hydroxide solution (3.0 mL) and 1,2-dimethoxyethane (6.0 mL) were added to the residue
9. stirringthe mixture was stirred
10. temperaturewith heating in a microwave reactor at 150° C. for 1 hr
11. customInsoluble material was removed by filtration
12. extractionthe mixture was extracted with ethyl acetate
13. dry with materialdried over anhydrous sodium sulfate
14. customInsoluble material was removed by filtration
15. concentrationthe filtrate was concentrated under reduced pressure
16. customThe residue was purified by basic silica gel column chromatography (ethyl acetate/hexane)