Triethylamine → 1-(Pyridin-4-yl)piperidin-4-one

Participants

Reaction Conditions

Reaction Steps

A solution of 4-chloropyridine hydrochloride (10 g), 1,4-dioxo-8-azaspiro[4,5]decane (10 g) and triethylamine (29 ml) in a mixture of ethanol (10 ml) and water (30 ml) was stirred at 150° C. for 22 hours in a sealed tube. After completion of the reaction, the solvent was evaporated and 5N aqueous sodium hydroxide solution (25 ml) was added. The mixture was extracted with a mixed solvent of chloroform-methanol (10:1). The organic layer was dried over anhydrous sodium sulfate and the solvent was evaporated. To the obtained residue was dropwise added conc. hydrochloric acid (30 ml) with ice-cooling, and the mixture was stirred at the same temperature for 10 min. After completion of the reaction, sodium hydroxide (15 g) was added. The mixture was extracted with chloroform and dried over anhydrous sodium sulfate. The solvent was evaporated and the obtained residue was purified by silica gel column chromatography (chloroform:methanol=9:1, 1% aqueous ammonia) and dried under reduced pressure to give the title compound (6.1 g).

Provenance & Evidence