反应详情

A mixture of 2-hydroxymethyl-1-(3-methyl-butyl)-1H-benzoimidazole-5-carboxylic acid (2.4 g, 9.1 mmol) and concentrated sulfuric acid (1.1 g, 10.9 mmol) in methanol (30 mL) was heated at reflux for 40 hrs. The solution was cooled to room temperature, the pH adjusted to 8-9 with concentrated ammonia, and water was added. A white precipitate formed that was collected by filtration and washed with water. The product was dried in vacuo to yield 2-hydroxymethyl-1-(3-methyl-butyl)-1H-benzoimidazole-5-carboxylic acid methyl ester (2.4 g, 96%) as a white solid.

1. temperaturewas heated
2. temperatureat reflux for 40 hrs
3. additionwas added
4. customA white precipitate formed
5. filtrationthat was collected by filtration
6. washwashed with water
7. customThe product was dried in vacuo