Methyl 4-hydroxy-4-(2,3,4-trimethoxyphenyl)-2-butynoate → Methyl 3-(2,3,4-trimethoxybenzoyl)propiolate
反応式
[OH:1][CH:2]([C:9]1[CH:14]=[CH:13][C:12]([O:15][CH3:16])=[C:11]([O:17][CH3:18])[C:10]=1[O:19][CH3:20])[C:3]#[C:4][C:5]([O:7][CH3:8])=[O:6]>C(Cl)Cl.[O-2].[O-2].[Mn+4]>[CH3:20][O:19][C:10]1[C:11]([O:17][CH3:18])=[C:12]([O:15][CH3:16])[CH:13]=[CH:14][C:9]=1[C:2]([C:3]#[C:4][C:5]([O:7][CH3:8])=[O:6])=[O:1]参加物
4
実験手順
A solution of 7 g (25 mmol) of methyl 4-hydroxy-4-(2,3,4 -trimethoxyphenyl)-2-butynoate in 40 ml of methylene chloride was added dropwise at 0° to a suspension of 62 g (0.71 mol) of manganese dioxide in 140 ml of methylene chloride. The reaction mixture was stirred at 0° for 1 hour, filtered over magnesium sulphate and concentrated. Crystallization of the residue from ethyl acetate/hexane yielded methyl 3-(2,3,4 -trimethoxybenzoyl)propiolate of melting point 74°.