Methanol → 6-Chloropyridine-3-carbaldehyde

To a cooled 5° C., stirred solution of 2-chloro-5-cyanopyridine (25.0 grams) in anhydrous toluene (540 mL) was added a 1M solution of diisobutylaluminum hydride (189 mL) over a 30 minute period. The resulting red-colored solution was treated with methanol (50 mL) and 2M sulfuric acid (150 mL), sequentially. The resulting biphasic solution was allowed to warm to ambient temperature and stirred for 1 hour. The reaction mixture was extracted with ethyl acetate, the combined organic layers were washed with saturated aqueous sodium bicarbonate and saturated aqueous brine. The organic phase was stirred over activated charcoal for 20 minutes, dried over anhydrous sulfate and concentrated in vacuo to afford the title compound as a light-yellow colored solid, 23.5 grams 1H NMR (400 MHz, CDCl3) δ=10.08 (s, 1H); 8.85 (s, 1H); 8.12 (d, 1H); 7.50 (d, 1H).

1. extractionThe reaction mixture was extracted with ethyl acetate
2. washthe combined organic layers were washed with saturated aqueous sodium bicarbonate and saturated aqueous brine
3. stirringThe organic phase was stirred over activated charcoal for 20 minutes
4. dry with materialdried over anhydrous sulfate
5. concentrationconcentrated in vacuo

ORD record

ord-1fd3d0af30744885984b343054b69b0c

Source dataset

uspto-grants-2003_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06518431B2