反应详情

温度

0 °C

To a solution of 6-benzyloxy-3-)3-carboxyphenylmethylene)-4-chromanone from Step 2 (1.54 g, 3.8 mmol) in 40 ml THF/MeOH (1:3) was added 150 mg of 10% Pd/C. The mixture was hydrogenated at 40 psi for 20 hr. The mixture was filtered through celite. The filtrate was evaporated to dryness and redissolved in THF. The THF solution was cooled to 0° C. and diazomethane was added until no acid remained. Then HOAc was added. The mixture was evaporated to give an oil which was chromatographed on silica gel and eluted with 40% EtOAc/hexane to give 750 mg (63%) of the title compound.

1. filtrationThe mixture was filtered through celite
2. customThe filtrate was evaporated to dryness
3. dissolutionredissolved in THF
4. additiondiazomethane was added until no acid
5. additionThen HOAc was added
6. customThe mixture was evaporated
7. customto give an oil which
8. customwas chromatographed on silica gel
9. washeluted with 40% EtOAc/hexane