Hydrogen Bromide → 3-(Furan-2-yl)-acryloylpiperazine

Participants

Reaction Steps

To a homogeneous solution of 15.6 g. (80 mM) of piperazine hexahydrate and 13.8 g. (80 mM) of 47% hydrobromic acid in 40 ml. of ethanol there were added dropwise at room temperature another solution of 6.3 g. (40 mM) of 3-(Furan-2-yl)-acryloylchloride in 10 ml. of tetrahydrofuran. After stirring for two hours at room temperature, the resulting solution was heated at 80° for two hours. Then the solution was cooled with ice and the forming crystals of piperazine hydrobromide were filtered off. The filtrate was condensed under reduced pressure and 80 ml. of 2 N-hydrochloric acid was added into the residue. After neutral substances were removed by extraction with ethyl acetate, the resulting solution was made alkaline with 5 N sodium hydroxide and extracted again with ethyl acetate. After drying over anhydrous sulfate, the combined extracts were condensed to give 4.62 g. of 3-(Furan-2-yl)-acryloylpiperazine (56% yield).

Provenance & Evidence