Hydrogen Bromide → KOJIC ACID, 2-BROMOMETHYL ANALOG
반응식
[OH:1][C:2]1[C:3](=[O:10])[CH:4]=[C:5]([CH2:8]O)[O:6][CH:7]=1.OS(O)(=O)=O.[BrH:16].[OH-].[Na+]>>[Br:16][CH2:8][C:5]1[O:6][CH:7]=[C:2]([OH:1])[C:3](=[O:10])[CH:4]=1참가 물질
5
반응 조건
- 온도
- 4 °C
실험 절차
In a 250 mL round-bottomed flask 5-hydroxy-2-(hydroxymethyl)-4H-pyran-4-one (10.0 g, 70.36 mmol) was added to concentrated H2SO4 (30 mL). The solution was cooled to 4° C. and bromohydric acid (40 mL) was added dropwise for 1.5 h. HBr vapors were trapped using a NaOH 0.5 N solution. The reaction was stirred at 70° C. for 18.5 h. After cooling ice (220 g) was added with continuous stirring for for 1.5 h to obtain a white precipitate. The solid was filtered off and dissolved in ethyl acetate and the solution was dried with MgSO4, filtered and evaporated. 2-(Bromomethyl)-5-hydroxy-4H-pyran-4-one 21 was obtained as a pale yellow solid (9.1 g, 63% yield).