Diethylene Glycol Monoethyl Ether → 3-Oxo-2-(4-tert-butylphenyl)-3-(1,3,4-trimethylpyrazol-5-yl)propionitrile

Participants

Reaction Conditions

Reaction Steps

In a 10 L-reaction flask equipped with a rectification column and a separating tank, 314 g (1.81 mol) of 4-tert-butylphenylacetonitrile, 300 g (1.65 mol) of 1,3,4-trimethylpyrazol-5-carboxylic acid ethyl ester, 3000 g of heptane, 225 g of diethylene glycol dimethyl ether, and 99 g of diethylene glycol monoethyl ether were added, the atmosphere was substituted with nitrogen, then azeotropic dehydration was carried out by heating at 90 to 95° C. for 1 hour. The temperature was maintained, 381 g (1.98 mol) of 28% sodium methoxide methanol solution was added dropwise over 10 hours, and the resulting mixture was further reacted for 7 hours. After cooling to 30° C. or less, 3000 g of water was added to separate out heptane phase, and the resulting aqueous phase was further washed with 600 g of heptane to separate out heptane phase. A quantitative analysis of the obtained aqueous phase with liquid chromatography showed that the aqueous phase contained 466 g (yield 91.5%) of 2-(4-tert-butylphenyl)-3-(1,3,4-trimethyl-5-pyrazolyl)-3-oxopropionitrile. After adding 2760 g of xylene to the aqueous phase, 206 g (1.98 mol) of 35% hydrochloric acid was added dropwise to be neutralized. After separating out the aqueous phase, the resulting organic phase was washed two times with 600 g of water and the aqueous phase was separated out to obtain xylene solution of 3-oxo-2-(4-tert-butylphenyl)-3-(1,3,4-trimethylpyrazol-5-yl) propionitrile. A quantitative analysis with liquid chromatography showed that the xylene solution contained 456 g (yield 89.6%) of 3-oxo-2-(4-tert-butylphenyl)-3-(1,3,4-trimethylpyrazol-5-yl) propionitrile.

Provenance & Evidence