Pyridinium, 1-fluoro-, 1,1,1-trifluoromethanesulfonate (1:1) → 2-[5-(3-bromophenyl)-2H-tetrazol-2-yl]pyridine

Temperature

-78 °C

5-(3-Bromophenyl)-2H-tetrazole (448 mg, 2.0 mmol) was stirred in anhydrous MeOH (15 mL) under argon at ambient temperature. To this was added NaOMe (4 mL of 0.5M solution in MeOH, 2.0 mmol), and the reaction flask was cooled to −78° C. A solution of N-fluoropyridinium triflate (331 mg, 1.0 mmol) in anhydrous MeOH (2 mL) was then added dropwise via syringe. The resulting reaction mixture was stirred at −78° C. for 30 min, then warmed to ambient temperature and stirred for an additional 3 h. The reaction mixture was partitioned between EtOAc (150 mL) and 10% aqueous NaHCO3 (50 mL). The EtOAc layer was washed with additional 10% aqueous NaHCO3 (2×50 mL), and the combined aqueous layers were back extracted with EtOAc (100 mL). The EtOAc layers were combined, dried (MgSO4), filtered and concentrated in vacuo. The crude material was then chromatographed on silica gel eluting with hexanes:EtOAc (3:1) to afford 2-[5-(3-bromophenyl)-2H-tetrazol-2-yl]pyridine as a white solid.

1. customThe resulting reaction mixture
2. temperaturewarmed to ambient temperature
3. stirringstirred for an additional 3 h
4. customThe reaction mixture was partitioned between EtOAc (150 mL) and 10% aqueous NaHCO3 (50 mL)
5. washThe EtOAc layer was washed with additional 10% aqueous NaHCO3 (2×50 mL)
6. extractionthe combined aqueous layers were back extracted with EtOAc (100 mL)
7. dry with materialdried (MgSO4)
8. filtrationfiltered
9. concentrationconcentrated in vacuo
10. customThe crude material was then chromatographed on silica gel eluting with hexanes:EtOAc (3:1)

ORD record

ord-e6d6be20b8624c1bbe670d45f6d0620c

Source dataset

uspto-grants-2007_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07253190B2