反应详情

温度

40 °C

36.6 g of Ac2O, 60 g of Et3N and 600 g of CH2Cl2 were placed in a flask and heated at 40° C. 36.6 of isocinchomeronic acid-N-oxide was added in portions. After a further 1.5 hours, NaOH (10 percent) was added while strongly stirring until the final pH reached 13. The phases were separated. The CH2Cl2 -solution was dried with solid NaOH and was kept for the next batch. The aqueous solution was acidified with concentrated HCl (final pH was about 2). The product obtained hereby was sucked off, washed and dried. The yield was 54.2 percent of 2-chlor-5-pyridine carboxylic acid (6-chloronicotinic acid) and 37.7 percent of 2-hydroxy-5-pyridine carboxylic acid (6-hydroxynicotinic acid).

1. customThe phases were separated
2. dry with materialThe CH2Cl2 -solution was dried with solid NaOH
3. customThe product obtained hereby
4. washwashed
5. customdried