4-Methylpyridine → 1-Pyridin-4-ylbutan-2-one

Participants

Reaction Steps

19.8 g of propionyl chloride dissolved in 20 ml of dichloromethane was added dropwise over 1 hour to 10 gm of 4-methylpyridine dissolved in 50 ml dichloromethane and maintained below 10° C. After addition, the reaction was brought to ambient temperature, stirred for 8 hours, then brought to reflux for 1 hour. The reaction mixture was quenched into saturated sodium carbonate solution, the organic layer separated and the solvent removed under reduced pressure. The residual 4-methylpyridine was removed by azeotropic distillation under reduced pressure with toluene. Ethanol was added and the mixture refluxed for 6 hours. The solvent was removed under reduced pressure to give 4.45 g of good (4-pyridinylmethyl) ethyl ketone.

Provenance & Evidence