Piperazine → HCID 19420475, compound

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Reaction Steps

Following the procedure of Example 6, but replacing 1-benzylpiperazine with 1-[4-nitrobenzyl]piperazine, provided the desired compound. To a solution of piperazine (2 g, 0.023 mol) in 10 mL of ethanol added a solution of 4-nitrobenzyl bromide (5 g, 0.023 mol) in 20 mL of warm ethanol. It was gently refluxed for 1 hour and stirred at room temperature for one over night. The resulting white precipitate was filtered, washed with a small amount of cold ethanol, and dried to yield 1-[4-nitrobenzyl]piperazine hydrobromide (3 g). MS m/z M+H=222, H1 --NMR (in MeOH-d4) δ=2.7 (t, 4H, piperazine), 3.25 (t, 4H, piperazine), 3.75 (s, 2H, benzyl), 7.62 (d, 2H, aromatic), 8.20 (d, 2H, aromatic). The obtained 1-[4-nitrobenzyl]piperazine hydrobromide (3 g, 9.93 mmol) was dissolved in 60 mL of 3N sodium hydroxide aqueous solution and stirred at room temperature for 30 minutes. The product was extracted with ethyl acetate (50 mL×3), and the combined ethyl acetate layer was washed with brine, dried over anhydrous sodium sulfate. Solvent was removed to obtain 1.7 g of 1-[4-nitrobenzyl]piperazine in 78% yield. MS m/z M+H=222, H1 -NMR (in MeOH-d4) δ=2.45 (t, 4H, piperazine), 2.90 (t, 4H, piperazine), 3.55 (s, 2H, benzyl), 7.52 (d, 2H, aromatic), 8.50 (d, 2H, aromatic).

Provenance & Evidence