[O:1]1[CH:5]=[CH:4][CH:3]=[C:2]1[CH:6]1OC(C)(C)C(C)(C)O1.BrC1[CH:28]=[CH:27][C:19]([C:20]([O:22][C:23]([CH3:26])([CH3:25])[CH3:24])=[O:21])=[CH:18][CH:17]=1.C(=O)([O-])[O-].[Na+].[Na+].O1CCOCC1>[Pd].C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.O>[O:1]1[CH:5]=[CH:4][CH:3]=[C:2]1[C:6]1[CH:28]=[CH:27][C:19]([C:20]([O:22][C:23]([CH3:24])([CH3:25])[CH3:26])=[O:21])=[CH:18][CH:17]=1A mixture of 2-(furan-2-yl)-4,4,5,5-tetramethyl-1,3-dioxolane (500 mg, 2.6 mmol), tert-butyl 4-bromobenzoate (512 mg, 2 mmol) and sodium carbonate (636 mg, 6 mmol), tetra(triphenylphosphine) palladium (115 mg, 0.1 mmol) in mixed solution of 1,4-dioxane (20 ml) and water (4 ml) was stirred for 15 hours at 90° C. under nitrogen atmosphere. After cooling to room temperature, the reaction mixture was concentrated to give a residue. The residue was purified by column chromatography (silica gel, petroleum ether/ethyl acetate=10:1) to give tert-butyl 4-(furan-2-yl)benzoate (400 mg, 82%) as a yellow oil. LRMS (M+H+) m/z: calcd 244.11. found 244. 1H NMR (300 MHz, CD3OD): δ 7.99-7.96 (m, 2H), 7.78-7.75 (m, 2H), 7.63-7.62 (m, 1H), 6.94-6.93 (m, 1H), 6.57-6.56 (m, 1H), 1.61 (s, 9H).
Wird geladen…