反应详情

A suspension of 23 g of 5,6-difluoro-2-benzimidazolethiol in 740 ml of alcohol was treated with 22.1 g of 2-chloromethyl-4-methoxy-3-methylpyridine hydrochloride. A solution of 10 g of sodium hydroxide in 350 ml of water was added dropwise thereto while cooling with ice, the mixture was left to boil at reflux overnight and then concentrated to about 1/3 of its volume in a vacuum. After the addition of 1200 ml of water the crystals were filtered off and thereupon washed thoroughly first with water and then with ether. There was obtained 5,6-difluoro-2-[[(4-methoxy-3-methyl-2-pyridyl)methyl]thio]benzimidazole of melting point 216°-218°.

1. temperaturewhile cooling with ice
2. waitthe mixture was left
3. temperatureat reflux overnight
4. concentrationconcentrated to about 1/3 of its volume in a vacuum
5. additionAfter the addition of 1200 ml of water the crystals
6. filtrationwere filtered off
7. washwashed thoroughly first with water