Tetrabutylammonium Fluoride → 3-Ethynyl-2-fluoropyridine

2-Fluoro-3-[(trimethylsilyl)ethynyl]pyridine (8.8 g, 0.046 mol) was dissolved in a mixture of tetrahydrofuran (20 mL) and water (2 mL). A 1.0 M solution of tetra-n-butylammonium fluoride (12 g, 0.046 mol) in THF (46 ml) was then added dropwise at 0° C., and the reaction mixture was stirred for 1 hour. The reaction was extracted with ethyl acetate, and the combined organic extracts were washed with brine (3×), dried over MgSO4 and concentrated. The crude was purified via column chromatography on silica gel (10% ethyl acetate:90% hexanes) to provide 4.8 g of the desired product. 1H NMR (400 MHz, CDCl3): δ 8.20 (m, 1H), 7.88-7.92 (m, 1H), 7.17-7.21 (m, 1H), 3.40 (s, 1H).

1. extractionThe reaction was extracted with ethyl acetate
2. washthe combined organic extracts were washed with brine (3×)
3. dry with materialdried over MgSO4
4. concentrationconcentrated
5. customThe crude was purified via column chromatography on silica gel (10% ethyl acetate:90% hexanes)

ORD record

ord-7e07298bc2ea4ce0b6c2b554e16a33b4

Source dataset

uspto-grants-2014_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08835423B2