Hydrochloric Acid → 953411-01-3

Temperature

-78 °C

To a solution of thieno[2,3-b]pyridine (0.50 g, 3.7 mmol) in THF (25 mL) at about −78° C. was added n-BuLi (1.6 M in hexane, 2.5 mL, 4.1 mmol) dropwise over about 10 min. After about 45 min, added triisopropyl borate (0.93 mL, 4.1 mol). Stirred for about 1 hour at about −78° C. then at about 0° C. for about 30 min. 10% aqueous HCl (10 mL) was added and the ice bath was removed. After about 30 min, EtOAc (30 mL) was added. The reaction mixture was filtered to remove a precipitate that was washed with additional water and EtOAc. The combined layers were separated and the aqueous layer was extracted with additional EtOAc (2×30 mL). The combined organic layers were washed with brine, dried over anhydrous Na2SO4, decanted, and concentrated to get a solid that was triturated with EtOAc and heptane then filtered to give thieno[2,3-b]pyridin-2-ylboronic acid (0.043 g, 6%); RP-HPLC (Table 1, Method g) Rt 1.67 min, m/z (ESI+) 180.1 (M+H)+.

1. waitat about 0° C. for about 30 min
2. customthe ice bath was removed
3. waitAfter about 30 min
4. additionEtOAc (30 mL) was added
5. filtrationThe reaction mixture was filtered
6. customto remove a precipitate that
7. washwas washed with additional water and EtOAc
8. customThe combined layers were separated
9. extractionthe aqueous layer was extracted with additional EtOAc (2×30 mL)
10. washThe combined organic layers were washed with brine
11. dry with materialdried over anhydrous Na2SO4
12. customdecanted
13. concentrationconcentrated
14. customto get a solid
15. customthat was triturated with EtOAc and heptane
16. filtrationthen filtered

ORD record

ord-d9254a06e9454698832816bc6fc054cc

Source dataset

uspto-grants-2011_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08008481B2