Propargyl bromide → 1-Methyl-4-(prop-2-yn-1-yl)piperazine

Participants

Reaction Steps

Propargyl bromide (23.8 g, 200 mmol) was added dropwise to a mixture of 1-methyl-piperazine (20 g, 200 mmol) and cesium carbonate (65 g, 200 mmol) in 350 mL of acetone. The mixture was stirred overnight under nitrogen at room temperature. The inorganic salts were then filtered off, and the solvent was removed. The residue was dissolved in saturated sodium bicarbonate solution and extracted with ethyl acetate. The organic extracts were then evaporated to give 7.5 g of 1-methyl-4-prop-2-ynyl-piperazine: mass spectrum (m/e): M+H 139.

Provenance & Evidence