Hydrochloric Acid → 2-[4-(4,6-Dimethyl-pyridin-2-yl)-piperazin-1-yl]-5-nitro-phenol

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Reaction Steps

Trifluoroacetic acid (5 mL) was added to 1-(2-benzyloxy-4-nitro-phenyl)-4-(4,6-dimethyl-2-pyridyl)piperazine (720 mg, 1.72 mmol) at between 0 and 5° C. followed by concentrated hydrochloric acid (2 mL). The mixture was heated at reflux for 16 h then cooled to between 0 and 5° C. and quenched with saturated sodium bicarbonate solution (30 mL). Chloroform (30 mL) was added and the mixture was stirred for 15 min. The organic phase was separated and the aqueous phase was extracted with chloroform (30 mL). The combined organic phases were washed with water (2×30 mL), brine (30 mL), dried over anhydrous sodium sulfate and concentrated in vacuo to give a crude residue. Trituration with petroleum ether afforded 2-[4-(4,6-dimethyl-2-pyridyl)piperazin-1-yl]-5-nitro-phenol (510 mg, 90%) as a brownish-yellow solid.

Provenance & Evidence