反应详情

Dihydropyran (20.5 mL) as added dropwise to a solution of 2-acetylbenzoimidazole (32 g) and p-toluenesulfonic acid (2 g) in dichloromethane (280 mL) at reflux. The reaction mixture was stirred at this temperature for 24 hours, then cooled and the insoluble materials were filtered off. The filtrate was concentrated to give 2-acetyl-1-(tetrahydropyran-2-yl)-benzoimidazole as an amber oil (51.8 g). TLC: (dichloromethane:methanol, 97:3) RF=0.80.

1. temperatureat reflux
2. temperaturecooled
3. filtrationthe insoluble materials were filtered off
4. concentrationThe filtrate was concentrated