Pentane → 6-(2-Fluorophenyl)pyridin-3-ol

Participants

Reaction Conditions

Reaction Steps

3.3 ml (26.6 mmol) of boron trifluoride diethylether complex were cooled to −15° C. Then 2.5 g (13.3 mmol) of 6-(2-fluoro-phenyl)-pyridin-3-ylamine in 5 ml of DME and, subsequently, 1.9 ml (15.9 mmol) of tert-butyl nitrite were added dropwise. Shortly after, a thick precipitate formed. The mixture was diluted with 8 ml of DME and 8 ml of dichloromethane and stirred in an ice bath for 2 h. After addition of 50 ml of pentane, the precipitate was filtered off, dried, and stirred in 50 ml of acetic anhydride at 100° C. for 1 h. After concentration, a sodium hydrogencarbonate solution was added, and the mixture was extracted with ethyl acetate. The combined organic phases were dried and evaporated. The residue was purified by chromatography (silica gel, n-heptane/ethyl acetate 5:1). The obtained product was stirred with a 15% aqueous potassium hydroxide solution and few methanol in an ice bath and subsequently for 2 h at room temperature. After neutralization with 2 N hydrochloric acid, the mixture was extracted with ethyl acetate, and the combined extracts were dried and evaporated. Yield: 871 mg.

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