反应详情

A suspension of 2-(4-chlorobenzyl)-4-methoxy-7-methylbenzimidazole (4.0 g) in 48% aqueous hydrobromic acid (400 ml) under nitrogen was heated at 130° for 5 h, then evaporated to dryness in vacuo. The residue was recrystallized from ethanol-ether to afford the title compound (3.95 g), m.p. 275°-277° C.

1. temperaturewas heated at 130° for 5 h
2. customevaporated to dryness in vacuo
3. customThe residue was recrystallized from ethanol-ether