Hydrochloric Acid → 3-Pyridin-2-yl-isoxazole-4-carboxylic acid ethyl ester

Participants

Reaction Steps

To a solution of N-chlorosuccinimide (54.7 g, 409 mmol) in DMF (1 L) was added pyridine-2-carbaldoxime (50 g, 409 mmol) portionwise and the resulting mixture was then stirred for 64 h at room temperature. To this solution was then added ethyl 3-(N,N-dimethylamino)acrylate (58.6 g, 409 mmol) and triethylamine (82.9 mL, 819 mmol) in chloroform (10 mL) and the resulting mixture was then stirred for 14 h at room temperature and poured onto a mixture of ice water and HCl (4 N, 100 mL) and extracted with ethylacetate. The organic extract was then washed with water, saturated aqueous sodium hydrogen carbonate solution, brine, dried with sodium sulfate, filtered and evaporated. Purification by distillation afforded the title product (58.9 g, 66%) which was obtained as a light brown liquid. Bp 125-127° C. at 0.4 mbar. MS: m/e=219.2 [M+H]+.

Provenance & Evidence