反应详情

A solution of 2,6-dichloroisonicotinic acid (38.4 g, 0.20 mole) in thionyl chloride (60 ml.) and cyclohexane (100 ml) containing a few drops of dimethylformamide is heated at 80° for three hours. The solution is cooled and excess thionyl chloride and cyclohexane are removed in vacuo. The residue is dissolved in chloroform (40 ml.) and added dropwise to a solution of t-butanol (50 ml.) and N,N-dimethylaniline (40 ml.). The solution is heated at reflux for six hours, cooled, diluted with diethyl ether and washed successively with water, water containing 4 ml. of concentrated sulfuric acid, water, dilute sodium carbonate solution and dried over anhydrous sodium sulfate. The solvent is removed under vacuum and the residue is crystallized from a minimum amount of methanol to give 24 g. of product, m.p. 79°-81°.

1. temperatureis heated at 80° for three hours
2. temperatureThe solution is cooled
3. customexcess thionyl chloride and cyclohexane are removed in vacuo
4. dissolutionThe residue is dissolved in chloroform (40 ml.)
5. additionadded dropwise to a solution of t-butanol (50 ml.) and N,N-dimethylaniline (40 ml.)
6. temperatureThe solution is heated
7. temperatureat reflux for six hours
8. temperaturecooled
9. additiondiluted with diethyl ether
10. washwashed successively with water, water containing 4 ml
11. dry with materialof concentrated sulfuric acid, water, dilute sodium carbonate solution and dried over anhydrous sodium sulfate
12. customThe solvent is removed under vacuum
13. customthe residue is crystallized from a minimum amount of methanol
14. customto give 24 g