Carbon tetrabromide → 5-(2,2-Dibromoethenyl)-3,3-dimethyl-2,3-dihydro-1-benzofuran

反応式

[CH3:1][C:2]1([CH3:13])[C:6]2[CH:7]=[C:8]([CH:11]=O)[CH:9]=[CH:10][C:5]=2[O:4][CH2:3]1.C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.[C:33](Br)(Br)([Br:35])[Br:34]>C1COCC1>[Br:34][C:33]([Br:35])=[CH:11][C:8]1[CH:9]=[CH:10][C:5]2[O:4][CH2:3][C:2]([CH3:13])([CH3:1])[C:6]=2[CH:7]=1

参加物

実験手順

To a solution of 3,3-dimethyl-2,3-dihydro-1-benzofuran-5-carbaldehyde (4.18 g, 23.7 mmol) and triphenylphosphine (15.5 g, 59.3 mmol) in THF (40 mL) was added carbon tetrabromide, and the mixture was stirred at room temperature for 15 min. The solvent was evaporated under reduced pressure and the obtained residue was purified by silica gel column chromatography (hexane:ethyl acetate=49:1 to 7:3) to give the title compound (5.75 g, yield 73%) as an oil.