Heptane → 2-(2-Phenyl-5-ethyl-1,2,3-triazol-4-yl)-3-(1,3,4-trimethyl-5-pyrazolyl)-3-oxopropionitrile

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Reaction Conditions

Reaction Steps

In a 2 L-reaction flask equipped with a rectification column, 106 g (0.5 mol) of 2-phenyl-4-cyanomethyl-5-ethyl-1,2,3-triazole, 91 g (0.5 mol) of 1,3,4-trimethylpyrazol-5-carboxylic acid ethyl ester, 530 g of heptane, and 106 g of diethylene glycol dimethyl ether were added, then azeotropic dehydration was carried out by heating at 90 to 95° C. Thereafter 61.7 g (0.55 mol) of potassium-tert-butoxide was carefully added under nitrogen atmosphere, then the resulting solution was heated at 95° C. and reacted for 15 hours while removing the eluent from the rectification column. 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 into phases. A quantitative analysis of the obtained aqueous phase with liquid chromatography showed that the aqueous phase contained 118.5 g (yield 68%) of 2-(2-phenyl-5-ethyl-1,2,3-triazol-4-yl)-3-(1,3,4-trimethyl-5-pyrazolyl)-3-oxopropionitrile. The aqueous solution was warmed at 40° C., pH was adjusted to 1 by adding 35% hydrochloric acid with stirring. The crystal obtained by cooling to 15° C. over 2 hours was filtered. The crystal cake was washed three times with 200 ml of water and then dried to obtain 116 g (yield 66.5%) of 2-(2-phenyl-5-ethyl-1,2,3-triazol-4-yl)-3-(1,3,4-trimethyl-5-pyrazolyl)-3-oxopropionitrile (melting point 119° C.).

Provenance & Evidence