反应详情

A suspension of 5 g of β-carbolin-3-carboxylic acid in a mixture of 900 ml of tetrahydrofuran and 3.6 ml of triethylamine is boiled under reflux for 15 minutes and cooled to room temperature. Freshly distilled ethyl chloroformate (2.5 ml), dissolved in 100 ml of tetrahydrofuran, is added dropwise with stirring over a period of 11/2 hours. After the reaction mixture has been stirred for an additional 30 minutes, a large excess of methylamine is added. Stirring is continued for one hour, whereafter the mixture is filtered and concentrated to approximately 50 ml under reduced pressure. Addition of water (250 ml) causes the amide to precipitate. The mixture is left at 5° C. overnight, filtered and dried at 60° C. for 15 hours. β-carbolin-3-carboxylic acid methylamide thus formed (4.1 g; 77%) is recrystallized from toluene. The melting point is 275° C.

1. temperatureunder reflux for 15 minutes
2. additionis added dropwise
3. stirringStirring
4. waitis continued for one hour, whereafter the mixture
5. filtrationis filtered
6. concentrationconcentrated to approximately 50 ml under reduced pressure
7. additionAddition of water (250 ml)
8. customto precipitate
9. waitThe mixture is left at 5° C. overnight
10. filtrationfiltered
11. customdried at 60° C. for 15 hours