Sulfuric Acid → Methyl 4-[2-fluoro-3-(methylsulfonyl)phenyl]piperazine-1-carboxylate

関与物質

反応条件

反応手順

To an ice cooled solution of methyl 4-[2-fluoro-3-(methylthio)phenyl]piperazine-1-carboxylate (1.4 g, 4.9 mmol) in sulfuric acid (1 M, 10 ml) was added sodium tungstate (0.016 g, 0.05 mmol) in one portion followed by dropwise addition of hydroperoxide (30%, 1.25 ml, 12.2 mmol). The reaction mixture was warmed to 55° C. and was stirred for 20 h. The reaction mixture was brought to ambient temperature and aqueous sodium hydroxide (5 M, 50 ml) was added. The aqueous phase was extracted with ethyl acetate (2×50 ml). The combined organic phase was dried (MgSO4) and evaporated to dryness to give the title compound. Yield (1.1 g). MS m/z (rel. intensity, 70 eV) 316 (M+, 58), 296 (30), 228 (bp), 216 (38), 56 (71).

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