Potassium Carbonate → 4-(5-Bromopyridin-2-yl)piperidine-4-carbonitrile

Participants

Reaction Steps

1.0M Tetrahydrofuran-solution of sodium bis(trimethylsilyl)amide (19 ml) was added to 4-cyanopiperidine-1-carboxylic acid tert-butyl ester (3.23 g) at 0° C. and stirred for 50 minutes. A solution of 5-bromo-2-fluoropyridine (2.57 g) in tetrahydrofuran (5 ml) was added thereto and stirred at room temperature for 7.5 hours. An aqueous solution of potassium carbonate was added to the reaction solution and extracted with ethyl acetate. The organic layer was dried over anhydrous sodium sulfate and concentrated in vacuo. 2N Hydrochloric acid-ethanol solution (30 ml) was added to the residue and stirred for 4.5 hours. An aqueous solution of sodium bicarbonate was added to the reaction solution, extracted with ethyl acetate, and then with chloroform, washed with saturated brine dried over anhydrous sodium sulfate and concentrated in vacuo. The resulting solid was washed with isopropylether to give 4-(5-bromopyridin-2-yl)piperidine-4-carbonitrile (2.73 g) as a pale orange solid

Provenance & Evidence