反应详情

A degassed mixture of the product of Step 4 (2.0 g, 6.0 mmol) and 4-tributylstannylpyridine (2.5 g, 6.8 mmol) in toluene (100 ml) was treated with triphenylphosphine (156 mg, 0.6 mmol) and palladium acetate (67 mg, 0.3 mmol) then heated under reflux for 60 hours. The reaction mixture was concentrated in vacuo and the product purified by silica gel chromatography eluting with ethyl acetate/hexane (1:1) and then ethyl acetate to give the title compound (1.37 g, 69%); MS(ES+) m/e 333 [M+H]+.

1. temperaturethen heated
2. temperatureunder reflux for 60 hours
3. concentrationThe reaction mixture was concentrated in vacuo
4. customthe product purified by silica gel chromatography
5. washeluting with ethyl acetate/hexane (1:1)