反应详情

温度

110 °C

A mixture of the product of Example 44, step C (1.41 g, 3.14 mmol), di-palladium-tris(dibenzylideneacetone) (575 mg, 0.62 mmol), potassium hydroxide (387 mg, 6.91 mmol) and 2-(di-tert-butylphosphino)-2′,4′,6′-triisopropyl-3,4,5,6-tetramethyl-1,1′-biphenyl (121 mg, 0.25 mmol) in water (14 mL) and 1,4-dioxane (14 mL) was heated to 110° C. for 24 h. After cooling to ambient temperature, the reaction mixture was neutralized with 1N aqueous HCl, filtered through celite bed and extracted with ethyl acetate (4×30 mL). The combined organic extracts were washed with brine, dried over Na2SO4 and concentrated in vacuo to give the crude product which was purified by column chromatography (SiO2, 7:3 hexanes/ethyl acetate) providing tert-butyl 6-hydroxy-8-phenylsulfonyl-3,4-dihydrobenzofuro[3,2-c]pyridine-2(1H)-carboxylate (470 mg, 34%): 1H NMR (CDCl3, 300 MHz) δ 7.93-7.90 (m, 2H), 7.62 (br s, 1H), 7.55-7.43 (m, 3H), 7.39 (d, J=1.8 Hz, 1H), 4.54 (s, 2H), 3.81 (t, J=5.4 Hz, 2H), 2.83 (t, J=5.7 Hz, 2H), 1.51 (s, 9H).

1. temperatureAfter cooling to ambient temperature
2. filtrationfiltered through celite bed
3. extractionextracted with ethyl acetate (4×30 mL)
4. washThe combined organic extracts were washed with brine
5. dry with materialdried over Na2SO4
6. concentrationconcentrated in vacuo
7. customto give the crude product which
8. customwas purified by column chromatography (SiO2, 7:3 hexanes/ethyl acetate)