反应详情

3-Bromo-2-chloropyridine (7.27 g, 37.8 mmol), 5-aminopyridin-2-ol (4.99 g, 45.3 mmol), freshly ground cesium carbonate (36.9 g, 113 mmol), and DMSO (37.8 ml, 37.8 mmol) were added into a glass round bottom pressure vessel equipped with a stir bar. The vessel was sealed and placed in a preheated oil bath at 130° C. After 18 h, the reaction was diluted with EtOAc (4×250 mL) and the whole solution was sonicated. After the solid was settled, the top solution was decanted through a pad of celite and silica gel (each layer was 1 cm). This procedure was repeated for the salt residue which left in the flask to remove the product and DMSO from the salt. The filtrate was concentrated to give an oil which included the product and DMSO. The product was extracted with EtOAc (3×300 mL) and DCM (1×100 mL). The EtOAc and DCM layers were washed separately with a minimum amount of brine. The organic phases were dried separately over a minimum amount of MgSO4. The MgSO4 was filtered off and the filtrates were combined and concentrated. A wet, light green solid was obtained. The solid was triturated with hexanes. The solid was filtered off, collected, and dried under vacuum. The product, 6-(3-bromopyridin-2-yloxy)pyridin-3-amine was collected as tan solids. A second batch was obtained from the filtrate. The filtrate was concentrated to give an oil. The oil was purified by ISCO column chromatography using 90:10 DCM:(90:10:1 DCM:MeOH:NH4OH). A light yellow solid, was obtained, dried under vacuum, and given a sample ID: A wet, green solid was obtained, dried under vacuum. MS Calcd for C10H8BrN3O: [M]+=265. Found [M+1]+=266.

1. customequipped with a stir bar
2. customThe vessel was sealed
3. customplaced in a preheated oil bath at 130° C
4. customthe whole solution was sonicated
5. customthe top solution was decanted through a pad of celite and silica gel (each layer
6. waitleft in the flask
7. customto remove the product and DMSO from the salt
8. concentrationThe filtrate was concentrated
9. customto give an oil which
10. extractionThe product was extracted with EtOAc (3×300 mL) and DCM (1×100 mL)
11. washThe EtOAc and DCM layers were washed separately with a minimum amount of brine
12. dry with materialThe organic phases were dried separately over a minimum amount of MgSO4
13. filtrationThe MgSO4 was filtered off
14. concentrationconcentrated
15. customA wet, light green solid was obtained
16. customThe solid was triturated with hexanes
17. filtrationThe solid was filtered off
18. customcollected
19. customdried under vacuum
20. customThe product, 6-(3-bromopyridin-2-yloxy)pyridin-3-amine was collected as tan solids
21. customA second batch was obtained from the filtrate
22. concentrationThe filtrate was concentrated
23. customto give an oil
24. customThe oil was purified by ISCO column chromatography
25. customA light yellow solid, was obtained
26. customdried under vacuum
27. customA wet, green solid was obtained
28. customdried under vacuum