1-Piperazinecarboxaldehyde → 1-Cinnamoyl-4-formylpiperazine

Participants

Reaction Steps

trans-Cinnamic acid (1.48 g) and N-formylpiperazine (2.28 g) were dissolved in N,N-dimethylformamide (20 mL), and the atmosphere was purged with nitrogen. While the solution was stirred in an ice-water bath, triethylamine (2.53 g) and diphenylphosphoryl azide (5.78 g) were added thereto, and stirring was continued for 1 hour and 45 minutes. The reaction mixture was poured in a mixture of ice and saturated sodium hydrogencarbonate solution, followed by extraction twice with ethyl acetate. The organic layers were combined and sequentially washed with 1N hydrochloric acid, saturated sodium hydrogencarbonate solution, and saturated brine, followed by drying over sodium sulfate anhydrate. The solvent was removed under reduced pressure, and the residue (colorless, oily) was purified through silica gel chromatography (silica gel 45 g, eluent; chloroform:methanol=200:1-100:1). The thus-purified product was dissolved in ethyl acetate, and the solution was sequentially washed with saturated sodium hydrogencarbonate solution and saturated brine, followed by drying over sodium sulfate anhydrate. The solvent was removed under reduced pressure, to thereby yield 1.22 g of the product of interest as a colorless oil (yield 50.0%).

Provenance & Evidence