反应详情

Compound 20 (0.88 g, 3.2 mmol) and 2-furan boronic acid (0.54 g, 4.8 mmol) were dissolved in tetrahydrofuran (12 mL) and a 2 M-aqueous solution (4.0 mL) of sodium carbonate. To this solution, trans-bromo(N-succinimidyl)bis(triphenylphosphine)palladium(II) [trans-PdBr(N-Succ)(PPh3)2] (25.9 mg, 1.0 mol %) was added and heated to reflux for 3 hours. After cooling to room temperature and adding ether (50 mL) to the solution, the organic layer was washed with water (30 mL) and dried (over magnesium sulfate), and the solvent was distilled off. The obtained residue was subjected to silica gel column chromatography and elution with an n-hexane/ethyl acetate (20:1) solution followed by conventional hydrolysis with potassium hydroxide to give 0.36 g (43%) of compound (21a) of interest as white solid.

1. temperatureheated
2. temperatureto reflux for 3 hours
3. washthe organic layer was washed with water (30 mL)
4. dry with materialdried (over magnesium sulfate)
5. distillationthe solvent was distilled off
6. washThe obtained residue was subjected to silica gel column chromatography and elution with an n-hexane/ethyl acetate (20:1) solution
7. customfollowed by conventional hydrolysis with potassium hydroxide