Hydrochloric Acid → 2-(3-Bromo-4-(4-(thiophen-2-ylsulfonyl)piperazin-1-yl)phenyl)-1,1,1-trifluoro-2-propanol

関与物質

反応手順

A 250 mL round-bottomed flask was charged with tert-butyl 4-(2-bromo-4-(2,2,2-trifluoro-1-hydroxy-1-methylethyl)phenyl)-1-piperazinecarboxylate (3.70 g, 8.16 mmol), 25 mL of EtOAc, and 8 mL of 4M HCl in dioxane (32 mmol). After heating at reflux for 30 min, the mixture was cooled and concentrated. The resulting viscous oil was dissolved in 30 mL of CH2Cl2 and triethylamine (3.98 mL, 28.6 mmol). At 0° C., 2-thiophenesulfonyl chloride (1.49 g, 8.16 mmol, Sigma-Aldrich, St. Louis, Mo.) was added at 0° C. After 15 min, the mixture was concentrated then re-dissolved in 5 mL of CH2Cl2, filtered, and purified via column chromatography (120 g of silica, 0 to 50% EtOAc in hexanes) to give 2-(3-bromo-4-(4-(thiophen-2-ylsulfonyl)piperazin-1-yl)phenyl)-1,1,1-trifluoro-2-propanol (2.75 g) as a white solid.

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