Pyridinium chloride → (2E)-3-[4-(9a-butyl-7-hydroxy-3-oxo-2,3,9,9a-tetrahydro-1H-fluoren-4-yl)phenyl]-2-propenoic acid
반응식
[CH2:1]([C:5]12[CH2:17][CH2:16][C:15](=[O:18])[C:14]([C:19]3[CH:24]=[CH:23][C:22](/[CH:25]=[CH:26]/[C:27]([O:29]C)=[O:28])=[CH:21][CH:20]=3)=[C:13]1[C:12]1[C:7](=[CH:8][C:9]([O:31]C)=[CH:10][CH:11]=1)[CH2:6]2)[CH2:2][CH2:3][CH3:4].Cl.N1C=CC=CC=1>>[CH2:1]([C:5]12[CH2:17][CH2:16][C:15](=[O:18])[C:14]([C:19]3[CH:20]=[CH:21][C:22](/[CH:25]=[CH:26]/[C:27]([OH:29])=[O:28])=[CH:23][CH:24]=3)=[C:13]1[C:12]1[C:7](=[CH:8][C:9]([OH:31])=[CH:10][CH:11]=1)[CH2:6]2)[CH2:2][CH2:3][CH3:4]참가 물질
3
반응 조건
- 온도
- 190 °C
실험 절차
A mixture of methyl (2E)-3-[4-(9a-butyl-7-methoxy-3-oxo-2,3,9,9a-tetrahydro-1H-fluoren-4-yl)phenyl]-2-propenoate (60 mg, 92% weight pure, 0.128 mmol) and pyridine hydrochloride (741 mg, 6.41 mmol) was placed under a nitrogen atmosphere, heated in an oil bath at 190° C., and stirred. The reaction flask was periodically dipped deeper into the heating bath in order to melt the pyridine hydrochloride that condensed on the sides of the flask. After 2 hours at 190° C., the reaction mixture was cooled to room temperature and partitioned between EtOAc (10 mL) and water (10 mL). The aqueous phase was extracted with more EtOAc (2×5 mL). The combined EtOAc extracts were washed with brine, dried over MgSO4, filtered, and evaporated under vacuum to a yellow solid (55 mg). The crude product was suspended in EtOAc (10 mL) and extracted with 5% NaHCO3 (5 mL). The NaHCO3 solution was acidified with 2N HCl (2.5 mL) and extracted with EtOAc (2×5 mL). The latter EtOAc extracts were combined, washed with brine, dried over MgSO4, filtered, and evaporated under vacuum to a yellow solid (39.4 mg). This material was triturated with diethyl ether and dried under vacuum to afford (2E)-3-[4-(9a-butyl-7-hydroxy-3-oxo-2,3,9,9a-tetrahydro-1H-fluoren-4-yl)phenyl]-2-propenoic acid as a pale yellow solid.