Methanol → Tert-butyl 7-hydroxychromane-3-carboxylate

反応式

C([O:8][C:9]1[CH:18]=[C:17]2[C:12]([CH:13]=[C:14]([C:19]([O:21][C:22]([CH3:25])([CH3:24])[CH3:23])=[O:20])[CH2:15][O:16]2)=[CH:11][CH:10]=1)C1C=CC=CC=1.CO>C(OCC)(=O)C.[Pd]>[OH:8][C:9]1[CH:18]=[C:17]2[C:12]([CH2:13][CH:14]([C:19]([O:21][C:22]([CH3:25])([CH3:24])[CH3:23])=[O:20])[CH2:15][O:16]2)=[CH:11][CH:10]=1

参加物

実験手順

tert-butyl 7-(benzyloxy)-2H-chromene-3-carboxylate (13 g) was dissolved in ethyl acetate (15 ml) and methanol (5 ml) in a hydrogenation bottle. Pd—C (10%) (1 g) was added and the reaction mixture was hydrogenated (H2, 70 psi & RT) for overnight. After the completion of the reaction, catalyst was filtered and washed with 100 ml of ethyl acetate. Solvent was evaporated and the crude product was purified using column chromatography and ethyl acetate hexane mixture to give 6 g of pure product (48.3% overall for 2 steps).