Potassium Hydroxide → (E)-3-(5-{(E)-3-[4-(4-acetyl-piperazin-1-ylmethyl)-phenyl]-3-oxo-propenyl}-pyridin-2-yl)-acrylic acid

Participants

Reaction Steps

A mixture of 1-[4-(4-acetyl-benzyl)piperazin-1-yl]-ethanone (prepared following the procedure described in Preparation 12, 500 mg, 1.92 mmol), (E)-3-(5-formyl-pyridin-2-yl)-acrylic acid tert-butyl ester (described in Example 11 STEP A-D, 448 mg, 1.92 mmol) and 1.7 M KOH (1.2 ml) in EtOH (19 ml) was stirred at room temperature for 6 h and then partitioned between water and AcOEt. The organic phase was dried over Na2SO4 and evaporated in vacuo. The crude reaction mixture was purified by column chromatography (eluent: DCM/MeOH/NH4OH 97:3:0.1) and the resulting product was dissolved in DCM (1.5 ml) and TFA (0.560 ml). The solution was stirred at room temperature for 3 h and then the solvent was evaporated to give 300 mg (E)-3-(5-{(E)-3-[4-(4-acetyl-piperazin-1-ylmethyl)-phenyl]-3-oxo-propenyl}-pyridin-2-yl)-acrylic acid as its bis-trifluoroacetate salt (the compound was used without further purification in the next step).

Provenance & Evidence