Malononitrile → 2-((1-Benzyl-1H-pyrazol-4-yl)(hydroxy)methylene)malononitrile

Participants

Reaction Steps

A solution of 1-benzyl-1H-pyrazole-4-carboxylic acid (25.0 g, 123.8 mmol) in SOCl2 (250 mL) was heated to reflux for 3 hr. The mixture was concentrated in vacuum to give the intermediate, which was used in the next step without further purification. To a solution of propanedinitrile (8.2 g, 12.8 mmol), DIEA (32.0 g, 247.6 mmol) in THF (250 mL) was added dropwise a solution of intermediate in toluene (250 mL) at 0-5° C. over 1 hr. The resultant mixture was allowed to warm to RT and stirred for 16 hr. The reaction was quenched with water (500 mL) and extracted with EA (500 mL×3), The organic layers were washed with 3 N HCl (500 mL), brine (500 mL×3), dried over Na2SO4 and concentrated to give the crude product (26.5 g, 85.0%) as a yellow solid. MS (ESI) m/e [M+1]+ 250.9.

Provenance & Evidence