1,3-Propanediamine, N'-(ethylcarbonimidoyl)-N,N-dimethyl-, monohydrochloride → 5-({2-[4-(2-tert-butylphenyl)piperazin-1-yl]-2-oxoethyl}sulfanyl)-1,3-dimethyl-1H-pyrazole-4-carbaldehyde

Participants

Reaction Steps

A mixture of 1-(2-tert-butylphenyl)piperazine dihydrochloride obtained in Reference Example 1 (1.0 g), [(4-formyl-1,3-dimethyl-1H-pyrazol-5-yl)sulfanyl]acetic acid obtained in Reference Example 3 (736 mg), 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (786 mg), 1-hydroxy-1H-benzotriazole monohydrate (628 mg), triethylamine (1.39 mL), and N,N-dimethylformamide (50 mL) was stirred at room temperature for over-night. Water was added to the reaction solution, and the mixture was extracted with ethyl acetate. The ethyl acetate layer was washed with saturated brine, and dried over anhydrous magnesium sulfate. The solvent was evaporated under reduced pressure, and the residue was purified by flash column chromatography (silica gel, 80:20-30:70 hexane/ethyl acetate) to provide 5-({2-[4-(2-tert-butylphenyl)piperazin-1-yl]-2-oxoethyl}sulfanyl)-1,3-dimethyl-1H-pyrazole-4-carbaldehyde (900 mg, 64%) as a colorless oil.

Provenance & Evidence