Acetyl chloride → (4-Acetylmorpholin-2-yl)methyl 4-phenylpiperazine-1-carboxylate

Participants

Reaction Steps

To a stirred solution of morpholin-2-ylmethyl 4-phenylpiperazine-1-carboxylate dihydrochloride (Example 10; 0.52 g, 1.40 mmol) in pyridine (2.25 mL, 27.7 mmol) was slowly added acetyl chloride (0.15 mL, 2.10 mmol). The reaction mixture was stirred at room temperature for 1 h before the pyridine was removed in vacuo and the resulting residue diluted with sat aq NaHCO3 solution (50 mL). The organic product was extracted with EtOAc (3×50 mL). The combined organic layers were washed with sat aq NaHCO3 solution (3×50 mL), dried (MgSO4) and the solvent removed in vacuo. The residue was purified by column chromatography (normal phase, 20 g, Strata SI-1, silica gigatube, 20 mL/min, gradient 0% to 5% MeOH in EtOAc). The solvents were removed in vacuo and dried in a vacuum oven overnight to afford (4-acetylmorpholin-2-yl)methyl 4-phenylpiperazine-1-carboxylate (0.38 g, 78%) as a pale brown oil.

Provenance & Evidence