反应详情

A stirred mixture of benzeneboronic acid (0.610 g; 5 mmol), 5-bromo-2,3-dimethoxybenzaldehyde (1.00 g; 4.1 mmol), bis(triphenylphosphine)palladium (II) chloride (0.050 g; 0.071 mmol), sodium carbonate (0.848 g; 8 mmol), isopropanol (40 mL) and water (4.0 mL) was bubbled with nitrogen for fifteen minutes then heated under reflux overnight. The mixture was evaporated, the residue stirred with water and dichloromethane and the organic layer dried and evaporated. The residue was taken up in boiling cyclohexane (40 mL twice) and filtered hot. The solution was chromatographed on silica using cyclohexane to elute triphenylphosphine and 10% ethyl acetate—90% cyclohexane to elute product 21 (0.87 g) as a white crystalline solid:

1. customwas bubbled with nitrogen for fifteen minutes
2. temperaturethen heated
3. temperatureunder reflux overnight
4. customThe mixture was evaporated
5. customthe organic layer dried
6. customevaporated
7. filtrationfiltered hot
8. customThe solution was chromatographed on silica
9. washto elute triphenylphosphine and 10% ethyl acetate—90% cyclohexane
10. washto elute product 21 (0.87 g) as a white crystalline solid