Potassium Fluoride → 2-[5-(Fluoromethyl)isoxazol-3-yl]but-3-yn-2-ol

Participants

Reaction Steps

To a solution of [3-(2-hydroxybut-3-yn-2-yl)isoxazol-5-yl]methyl 4-methylbenzenesulfonate (259 mg, 0.81 mmol) in dry acetonitrile (10 mL) was introduced potassium fluoride (94 mg, 1.61 mmol) and Kryptopfix® 222 (606 mg, 1.61 mmol). After 5 hr rapid stirring at RT, the reaction mixture was concentrated in vacuo and the residue partitioned between EtOAc (40 mL) and water (2×40 mL). The organic extract was washed with brine (30 mL), dried (Na2SO4), filtered and the filtrate adsorbed onto silica gel in vacuo. Purification by silica gel flash column chromatography (heptane/EtOAc gradient of increasing polarity) furnished the title compound as a colorless oil: 1H NMR (500 MHz, CDCl3) delta 1.91 (3H, s), 2.69 (1H, s), 2.86 (1H, s), 5.42 (1H, d, J=47.3 Hz), 6.55 (1H, d, J=2.8 Hz); 19F NMR-decoupled (235 MHz, CDCl3) delta −218.8 (s); LC-MS: m/z=+169.9 (M+H)+.

Provenance & Evidence