Ethyl Acetate → 5-Bromopyridine-2-carbonitrile

Temperature

40 °C

A stirred solution of 2,5-dibromopyridine (39.465 g, 0.17 mol) in anhydrous NMP (100 mL) was treated with CuCN (14.42 g, 0.17 mol) for 20 hours at 110° C. under nitrogen. The reaction mixture was cooled to 40° C. and treated with aqueous sodium hydroxide (2M; 200 mL) and then with ethyl acetate (200 mL). The mixture was stirred for 1 hour and then filtered through Celite to remove the resulting precipitate. The retained solid was washed with aqueous sodium hydroxide (2M; 600 mL) and then with ethyl acetate (600 mL). The organic layers were combined and washed with aqueous ammonium hydroxide (5M; 800 mL), dried over magnesium sulfate, and evaporated to dryness under reduced pressure. The involatile residue was purified by chromatography on silica gel [elution gradient 1% to 7% of ethyl acetate in hexanes] to give the title compound (8.538 g, 28%), as a colorless amorphous solid.

1. filtrationfiltered through Celite
2. customto remove the resulting precipitate
3. washThe retained solid was washed with aqueous sodium hydroxide (2M; 600 mL)
4. washwashed with aqueous ammonium hydroxide (5M; 800 mL)
5. dry with materialdried over magnesium sulfate
6. customevaporated to dryness under reduced pressure
7. customThe involatile residue was purified by chromatography on silica gel [elution gradient 1% to 7% of ethyl acetate in hexanes]

ORD record

ord-746a69381cb548acbfa33ab1d8bdb906

Source dataset

uspto-grants-2009_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07498350B2