Potassium Carbonate → Methyl 5-bromo-3-methylbenzofuran-2-carboxylate
反応式
[Br:1][C:2]1[CH:3]=[CH:4][C:5]([OH:11])=[C:6]([C:8](=O)[CH3:9])[CH:7]=1.Br[CH2:13][C:14]([O:16][CH3:17])=[O:15].C(=O)([O-])[O-].[K+].[K+]>CN(C)C=O>[Br:1][C:2]1[CH:3]=[CH:4][C:5]2[O:11][C:13]([C:14]([O:16][CH3:17])=[O:15])=[C:8]([CH3:9])[C:6]=2[CH:7]=1参加物
5
実験手順
To a solution (100 mL) of 1-(5-bromo-2-hydroxyphenyl)ethanone (10.0 g) in N,N-dimethylformamide were added methyl bromoacetate (4.85 mL) and potassium carbonate (12.9 g), and the mixture was stirred overnight at room temperature. The insoluble material was filtered off, 1,8-diazabicyclo[5.4.0]undec-7-ene (6.95 mL) was added to the filtrate, and the mixture was stirred at 120° C. for 2 hr. 1N Hydrochloric acid was added to quench the reaction, and the mixture was extracted with ethyl acetate. The extract was washed with saturated brine, dried over magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (10% ethyl acetate/hexane) to give the title object compound (6.06 g, 48%) as a pale-brown solid.