HCID 23157235、化合物 → Methyl 7-bromo-2,2-dimethyl-2,3-dihydro-1-benzofuran-5-carboxylate
反応式
[Br:1][C:2]1[CH:3]=[C:4]([CH:9]=[C:10]([CH2:13][C:14]([CH3:16])=[CH2:15])[C:11]=1[OH:12])[C:5]([O:7][CH3:8])=[O:6]>C1(C)C=CC=CC=1.C(OCC)(=O)C>[Br:1][C:2]1[C:11]2[O:12][C:14]([CH3:16])([CH3:15])[CH2:13][C:10]=2[CH:9]=[C:4]([C:5]([O:7][CH3:8])=[O:6])[CH:3]=1参加物
4
実験手順
A solution of methyl 3-bromo-4-hydroxy-5-(2-methylprop-2-en-1-yl)benzoate (4.1 g, 14.4 mmol) and boron trifluoride diethyl ether complex (2.0 mL, 15.8 mmol) in toluene (30 mL) was stirred at 100° C. for 90 min. After cooling, the reaction solution was diluted with ethyl acetate, washed successively with water, aqueous sodium hydrogencarbonate solution and aqueous sodium chloride solution, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The residue was subjected to silica gel column chromatography (ethyl acetate:hexane=3:97-15:85) to give the title compound (3.05 g, yield 74%) as colorless prism crystals.