Hydrogen Peroxide → 3,5-dichloro-4-(2-(3-cyclopentyloxy-4-methoxyphenyl)-2-oxoethyl)pyridine-N-oxide

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

Aqueous 27.5% hydrogen peroxide (0.32 mL) is added to a solution of 3-cyclopentyloxy-4-methoxyphenyl 3,5-dichloropyrid-4-ylmethyl ketone (990 mg) in glacial acetic acid (13 mL). The reaction is heated at 80° C. for 8 hours then allowed to stand overnight at room temperature. A further aliquot of aqueous 27.5% hydrogen peroxide (0.32 mL) is added and the mixture heated at 80° C. for 2 hours. The reaction mixture is diluted with ethyl acetate (200 mL) and washed with saturated aqueous sodium bicarbonate until the washings remained basic. The mixture is washed with brine (50 mL), dried (MgSO4), concentrated and the residue recrystallized from a mixture of dichloromethane/ethyl acetate/heptane to give 3,5-dichloro-4-(2-(3-cyclopentyloxy-4-methoxyphenyl)-2-oxoethyl)pyridine-N-oxide as a yellow solid, m.p. 179°-180° C. [Elemental analysis: C,57.3; H,4.81; N,3.54; Cl,18.0%; calculated for C19 H19Cl2NO4 : C,57.59; H,4.83; N,3.53; Cl,17.89%.]

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