反应详情

To tert-butyl alcohol containing 3-cyano-4-isobutylbenzoic acid (8.5 g) and triethylamine (4.2 g) was added diphenylphosphoryl azide (11.5 g) at room temperature and the mixture was stirred at a refluxing temperature for 1 h. The solvent was evaporated under reduced pressure. To the residue was added aqueous potassium carbonate solution and the mixture was extracted with ethyl acetate. The organic layer was washed with saturated brine and dried over anhydrous sodium sulfate, after which the solvent was evaporated under reduced pressure. To the residue were added 6N hydrochloric acid (10 ml) and methanol (100 ml) and the mixture was stirred at a refluxing temperature for 1 h. The solvent was evaporated under reduced pressure. To the residue was added aqueous sodium hydroxide solution and the mixture was extracted with toluene. The organic layer was washed with saturated brine and dried over anhydrous sodium sulfate, after which the solvent was evaporated under reduced pressure. n-Hexane was added to the residue to allow crystallization. The crystals were recrystallized from a mixed solvent of diisopropyl ether-n-hexane to give the title compound (6.0 g), melting point: 68° C.

1. customThe solvent was evaporated under reduced pressure
2. additionTo the residue was added aqueous potassium carbonate solution
3. extractionthe mixture was extracted with ethyl acetate
4. washThe organic layer was washed with saturated brine
5. dry with materialdried over anhydrous sodium sulfate
6. customafter which the solvent was evaporated under reduced pressure
7. additionTo the residue were added 6N hydrochloric acid (10 ml) and methanol (100 ml)
8. stirringthe mixture was stirred at a refluxing temperature for 1 h
9. customThe solvent was evaporated under reduced pressure
10. additionTo the residue was added aqueous sodium hydroxide solution
11. extractionthe mixture was extracted with toluene
12. washThe organic layer was washed with saturated brine
13. dry with materialdried over anhydrous sodium sulfate
14. customafter which the solvent was evaporated under reduced pressure
15. additionn-Hexane was added to the residue
16. customcrystallization
17. customThe crystals were recrystallized from a mixed solvent of diisopropyl ether-n-hexane