2,5-Dibromopyridine → HCID 57803252, compound

Temperature

-78 °C

To a solution of 2,5-dibromopyridine (4.10 g, 17 mmol) in anhydrous toluene (250 mL) at −78° C. was dropwise added n-BuLi (1.6 M, 12 mL). After stirred at −78° C. for 2.5 hours, a solution of 1,4-dioxa-spiro[4.5]decan-8-one (2.73 g, 17 mmol) in methylene chloride (25 mL) was added into the reaction mixture, and the resulting mixture was stirred for additional one hour and allowed to warm up to room temperature slowly. The reaction mixture was poured into aqueous NaHCO3 (200 mL) and then extracted with EtOAc (2×50 mL). The organic extracts were combined, washed with saline solution (2×50 mL), dried over MgSO4, and concentrated in vacuo. The resulting solid was triturated with ether and the solid was collected by filtration. The ether solution was concentrated and the solid was chromatographed on silica gel, eluting with hexane/ethyl acetate (2 to 1) to give a pale yellow solid. Weight of combined solids: 4.26 g. LCMS: 316.10/314.10 (M+H+, 100%). 1HNMR: δ 8.6 (s, 1H), 7.82 (d, 1H), 7.38 (d, 1H), 4.6 (s, 1H), 4.0 (m, 4H), 2.2 (m, 4H), 1.7 (m, 4H).

1. customat −78° C.
2. stirringthe resulting mixture was stirred for additional one hour
3. temperatureto warm up to room temperature slowly
4. extractionextracted with EtOAc (2×50 mL)
5. washwashed with saline solution (2×50 mL)
6. dry with materialdried over MgSO4
7. concentrationconcentrated in vacuo
8. customThe resulting solid was triturated with ether
9. filtrationthe solid was collected by filtration
10. concentrationThe ether solution was concentrated
11. customthe solid was chromatographed on silica gel
12. washeluting with hexane/ethyl acetate (2 to 1)
13. customto give a pale yellow solid

ORD record

ord-e199a4bcbf7e43c3a73fd03070c47956

Source dataset

uspto-grants-2014_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08697870B2