反应详情

Carbon tetrabromide (0.116 g) was added to a solution of methyl 6-(benzenesulfonylmethyl)-2-hydroxy-3-(2-hydroxymethylfuran-3-yl)-benzoate (Intermediate 19, 0.1 g) and triphenyl phosphine (0.09 g) in DCM (3 mL) and the resultant solution was stirred at room temperature for 2 hours. The mixture was evaporated to dryness and the residue was dissolved in DMF (2 mL) and cesium carbonate (0.163 g) was added. The mixture was stirred for 1 hour at room temperature, then at 50° C. for 15 minutes. After cooling, the mixture was partitioned between ethyl acetate and water, the organic layer was separated, dried (Na2SO4) and filtered. The filtrate was evaporated to dryness and the residue was purified by chromatography on silica, eluting with a mixture of ethyl acetate and cyclohexane (25%) to give methyl 7-(benzenesulfonylmethyl)-4H-furo[2,3-c]chromene-6-carboxylate (0.019 g).

1. customThe mixture was evaporated to dryness
2. dissolutionthe residue was dissolved in DMF (2 mL)
3. additioncesium carbonate (0.163 g) was added
4. waitat 50° C. for 15 minutes
5. temperatureAfter cooling
6. customthe mixture was partitioned between ethyl acetate and water
7. customthe organic layer was separated
8. dry with materialdried (Na2SO4)
9. filtrationfiltered
10. customThe filtrate was evaporated to dryness
11. customthe residue was purified by chromatography on silica
12. washeluting with a mixture of ethyl acetate and cyclohexane (25%)