反应详情

A mixture of 2,4-dimethyl-7-oxo-4,7-dihydrothieno[3,2-b]pyridine-6-carboxylic acid (1.27 g), triethylamine (0.6 ml) and dry tetrahydrofuran (120 ml) was stirred at ambient temperature for 30 minutes. The mixture was cooled to 0° and a solution of ethyl chloroformate (0.6 ml) in dry tetrahydrofuran (10 ml) was added during 3 minutes, before being allowed to warm to ambient temperature. Stirring was continued for 18 hours and a further quantity of ethyl chloroformate (0.3 ml) was added at ambient temperature. After stirring for a further 2 hours, the mixture was cooled to 5° and aqueous ammonia (specific gravity 0.880, 10 ml) was added. The mixture was stirred for 20 minutes and the solid was collected, washed with water (50 ml) and dried to give a second sample of crude 2,4-dimethyl-7-oxo-4,7-dihydrothieno[3,2-b]pyridine-6-carboxamide. The two samples of the carboxamide from (e) and (f) were combined and crystallised from industrial methylated spirit to give pure novel compound 2,4-dimethyl-7-oxo-4,7-dihydrothieno[3,2-b]pyridine-6-carboxamide, m.p. 328°-330°.

1. temperatureThe mixture was cooled to 0°
2. temperatureto warm to ambient temperature
3. stirringStirring
4. waitwas continued for 18 hours
5. stirringAfter stirring for a further 2 hours
6. temperaturethe mixture was cooled to 5°
7. stirringThe mixture was stirred for 20 minutes
8. customthe solid was collected
9. washwashed with water (50 ml)
10. customdried
11. customto give a second sample of crude 2,4-dimethyl-7-oxo-4,7-dihydrothieno[3,2-b]pyridine-6-carboxamide
12. customcrystallised from industrial methylated spirit