反应详情

m-Chloroperbenzoic acid (32.63 g) in dichloromethane (400 ml) was added dropwise to a solution of 3,4 -dichloro-2 -picoline (25.53 g)in dichloromethane (100 ml) maintaining the temperature at 20°-25°. After standing for 16 hours at room temperature the solution was washed with 1 N NAOH, dried (K2CO3 ) and filtered to give a pale yellow solution. Trifluoroacetic anhydride (30 ml) was added dropwise to this solution maintaining the temperature at 15°-20°. After standing for 2 days at room temperature, methanol (100 ml) was added and the solution evaporated under reduced presure. The residue was treated with aqueous sodium carbonate and extracted into dichloromethane. After drying (K2CO3 ) and removal of solvent, the residue was recrystallised from pet. ether (60/80 ) to give 3,4 -dichloro-2 -hydroxymethylpyridine, 15.76 g, m.p. 66°-8°.

1. temperaturemaintaining the temperature at 20°-25°
2. washthe solution was washed with 1 N NAOH
3. dry with materialdried (K2CO3 )
4. filtrationfiltered
5. customto give a pale yellow solution
6. temperaturemaintaining the temperature at 15°-20°
7. waitAfter standing for 2 days at room temperature
8. customthe solution evaporated under reduced presure
9. additionThe residue was treated with aqueous sodium carbonate
10. extractionextracted into dichloromethane
11. customAfter drying
12. custom(K2CO3 ) and removal of solvent
13. customthe residue was recrystallised from pet. ether (60/80 )