反応 #7832

反応方程式

3,5-dimethoxy-N-(2-methoxyphenyl)-4-methylbenzamide

p-toluenesulfonic acid monohydrate

→

2-(3,5-dimethoxy-4-methylphenyl)-1,3-benzoxazole

溶媒

toluene

反応条件

後処理

1. 1
   温度was refluxed until no starting material
2. 2
   ろ過filtered
3. 3
   洗浄washing with warm chloroform
4. 4
   その他Removal of solvent from filtrate
5. 5
   その他afforded a yellow solid
6. 6
   その他Purification of crude solid by flash chromatography on silica gel using 1:3 EtOAc

実験手順

A mixture of 3,5-dimethoxy-N-(2-methoxyphenyl)-4-methylbenzamide (1.29 g, 4.49 mmol), toluene (22 mL), p-toluenesulfonic acid monohydrate (5.9 g, 31 mmol) and molecular sieves was refluxed until no starting material was observed by TLC. Cooled mixture to rt and filtered, washing with warm chloroform. Removal of solvent from filtrate afforded a yellow solid. Purification of crude solid by flash chromatography on silica gel using 1:3 EtOAc:hexanes gave the desired intermediate, 2-(3,5-dimethoxy-4-methylphenyl)-1,3-benzoxazole, as a colorless solid.

出典