[CH3:1][O:2][C:3]1[C:11]2[O:10][C:9]([CH3:13])([CH3:12])[CH2:8][C:7]=2[CH:6]=[CH:5][CH:4]=1.[Br:14]N1C(=O)CCC1=O.O.C(OCC)C>CC1CCCO1>[Br:14][C:5]1[CH:4]=[C:3]([O:2][CH3:1])[C:11]2[O:10][C:9]([CH3:13])([CH3:12])[CH2:8][C:7]=2[CH:6]=156 g 7-methoxy-2,2-dimethyl-2,3-dihydro-1-benzofuran are dissolved in 200 ml 2-methyltetrahydrofuran, 58 g N-bromosuccinimide are added portion wise, while keeping the temperature of the reaction mixture below 50° C., and the reaction is stirred for one hour at RT. Water and diethyl ether are added to the reaction mixture, the phases are separated, the organic phase is washed with 1 M aqueous sodium carbonate solution, dried over MgSO4, and the solvent is removed under reduced pressure. The resulting crude product is purified by distillation under vacuum yielding 5-bromo-7-methoxy-2,2-dimethyl-2,3-dihydro-1-benzofuran.
読み込み中…
