Methanol → HCID 58636771、化合物
反応式
[CH:1]1([C:4]2[N:5]=[C:6]([CH3:12])OC=2OCC)[CH2:3][CH2:2]1.[C:13]([O:21][CH3:22])(=[O:20])/[CH:14]=[CH:15]\[C:16]([O:18][CH3:19])=[O:17].[CH3:23][OH:24]>>[CH3:19][O:18][C:16]([C:15]1[C:4]([CH:1]2[CH2:2][CH2:3]2)=[N:5][C:6]([CH3:12])=[C:23]([OH:24])[C:14]=1[C:13]([O:21][CH3:22])=[O:20])=[O:17]参加物
4
反応条件
- 温度
- 0 °C
実験手順
2-Cyclopropyl-5-ethoxy-4-methyl-oxazole (164) (33.8 g, 0202 mmol) in neat dimethyl maleate (115.8 g, 807 mmol) was refluxed for 4 hours. The reaction was cooled to 0° C., added anhydrous methyl alcohol (500 mL) and bubbled hydrogen chloride gas into the suspension for 15 minutes. The reaction flask was sealed with a rubber septum and kept in a fridge for overnight. The solid was filtered off and washed with methanol and diethyl ether. The filtrate was evaporated to give 2-cyclopropyl-5-hydroxy-6-methyl-pyridine-3,4-dicarboxylic acid dimethyl ester (165) (35.2 g, 66% yield) as a colorless solids.