反应详情

温度

50 °C

The 1-cyano-1-dimethylaminocarbonyl-4-dimethylamino-1,3-butadiene (14.5 g, 0.075 mol) obtained in (a) above was dissolved in 1,2-dichloroethane (150 ml) and the resulting solution heated to 50° C. The solution was then stirred whilst hydrogen chloride gas was introduced. After a few minutes, a thick mass of crystals formed in the solution which later dispersed to leave a deep red solution. After about 6 hours, no more starting material could be detected. Nitrogen was then introduced to blow the excess hydrogen chloride gas out of the solution and the solution was then extracted with water (4×100 ml). The organic phase was then dried over sodium sulphate and reduced in a vacuum. The residue was then stirred in petroleum ether, filtered off under suction and dried to give 10 g 2-chloropyridine-3-carboxylic acid N,N-dimethylamide as pale yellowish crystals, m.pt. 70°-71° C. Yield: 72% of the theoretical.

1. additionwas introduced
2. waitAfter a few minutes
3. customa thick mass of crystals formed in the solution which
4. additionlater dispersed
5. customto leave a deep red solution
6. additionNitrogen was then introduced
7. extractionthe solution was then extracted with water (4×100 ml)
8. dry with materialThe organic phase was then dried over sodium sulphate
9. filtrationfiltered off under suction
10. customdried