反应详情

1.16 g (3.8 mmol) of methyl 2-chloro-3-hydrazinocarbonyl-4-methylsulfonylbenzoate and 10 ml of triethyl orthoformate were heated under reflux for 6 hours. The precipitate that had formed was filtered off with suction, washed with n-hexane and subsequently taken up in 20 ml of toluene. After the addition of p-toluenesulfonic acid, the mixture was heated at reflux for 3 hours and then cooled, washed with water, dried and concentrated. 0.62 g (52% of thoery) of methyl 2-chloro-4-methylsulfonyl-3-(1,3,4-oxadiazol-2-yl)benzoate was obtained.

1. temperatureunder reflux for 6 hours
2. customThe precipitate that had formed
3. filtrationwas filtered off with suction
4. washwashed with n-hexane
5. additionAfter the addition of p-toluenesulfonic acid
6. temperaturethe mixture was heated
7. temperatureat reflux for 3 hours
8. temperaturecooled
9. washwashed with water
10. customdried
11. concentrationconcentrated