Hydrochloric Acid → 4-Chloro-2,6-dimethylpyridine

To a solution of concentrated HCl (10 ml) at 10° C. was added 2,6-dimethylpyridine N-oxide (3.0 g, 24.3 mmol) and the resulting white slurry was stirred at room temperature for 3 hours. The product was filtered and washed with iPrOH (2×10 ml) and dried at reduced pressure. The resulting solid was dissolved in POCl3 (10 ml) and heated at reflux for 8 hours then cooled to 0° C. The reaction was quenched carefully with saturated K2CO3 (40 ml) and extracted with dichloromethane (2×50 ml), dried (Na2SO4), filtered and concentrated at reduced pressure. The residue was dissolved in ethanol (20 ml) and NEt3 (5 ml) and heated at reflux for 24 hours then cooled to room temperature and concentrated at reduced pressure. Water (5 ml) was added to the residue the aqueous mixture was extracted with chloroform (2×10 ml). The organics were combined and washed with brine (10 ml), dried (Na2SO4), filtered and concentrated at reduced pressure to give the title compound as brown solid (1.0 g, 33%).

1. filtrationThe product was filtered
2. washwashed with iPrOH (2×10 ml)
3. customdried at reduced pressure
4. dissolutionThe resulting solid was dissolved in POCl3 (10 ml)
5. temperatureheated
6. temperatureat reflux for 8 hours
7. temperaturethen cooled to 0° C
8. customThe reaction was quenched carefully with saturated K2CO3 (40 ml)
9. extractionextracted with dichloromethane (2×50 ml)
10. dry with materialdried (Na2SO4)
11. filtrationfiltered
12. concentrationconcentrated at reduced pressure
13. dissolutionThe residue was dissolved in ethanol (20 ml)
14. temperatureNEt3 (5 ml) and heated
15. temperatureat reflux for 24 hours
16. temperaturethen cooled to room temperature
17. concentrationconcentrated at reduced pressure
18. additionWater (5 ml) was added to the residue the aqueous mixture
19. extractionwas extracted with chloroform (2×10 ml)
20. washwashed with brine (10 ml)
21. dry with materialdried (Na2SO4)
22. filtrationfiltered
23. concentrationconcentrated at reduced pressure

ORD 기록

ord-f91f4ce06f33465e9c2acd7ce3bb55da

출처 데이터셋

uspto-grants-2014_04

DOI

10.6084/m9.figshare.5104873.v1

특허 번호

US08691804B2