Chlorosulfonic acid → 7-Methyl-9-oxothioxanthene-3-carboxylic acid
反応式
[C:1]1([CH3:20])[CH:6]=[CH:5][C:4]([S:7][C:8]2[CH:13]=[C:12]([C:14]([OH:16])=[O:15])[CH:11]=[CH:10][C:9]=2[C:17]([OH:19])=O)=[CH:3][CH:2]=1.ClS(O)(=O)=O>O>[CH3:20][C:1]1[CH:2]=[C:3]2[C:4]([S:7][C:8]3[CH:13]=[C:12]([C:14]([OH:16])=[O:15])[CH:11]=[CH:10][C:9]=3[C:17]2=[O:19])=[CH:5][CH:6]=1参加物
4
反応条件
- 温度
- 10 °C
実験手順
The 2-(p-tolylthio)benzene-1,4-dicarboxylic acid is transferred slowly to a flask, containing 100 ml of chlorosulfonic acid. The temperature is maintained between the 5 and 10° C. with an ice-bath. At the end of the addition, the solution is left to rest for maturation and after 1 hour is poured in water and ice. The precipitate is filtered, washed with water and dried in a vacuum oven obtaining 19.69 g (yield: 96.7%) of 7-methyl-9-oxo-thioxanthene-3-carboxylic acid as a yellow solid. Melting point>250° C.