反应详情

A solution of 15.1 g of 2,6-dibromopyridine in 500 ml of triethylamine is mixed under ice cooling with 10.2 g of 3-ethinylbenzoic acid methyl ester, 1.1 g of bis-(triphenylphosphine)-palladium(II) chloride and 150 mg of copper(I) iodide and the mixture is stirred for 1 hour. Then, the ice bath is removed and it is stirred for 48 hours at room temperature. The precipitate is filtered off, the filtrate is evaporated to dryness, mixed with water and shaken out with ethyl acetate. The organic phase is dried on sodium sulfate, concentrated by evaporation and the residue is chromatographed on silica gel with hexane/0-12% ethyl acetate. 4.8 g of 2-bromo-6-[2-(3-methoxycarbonyiphenyl)-ethinyl]-pyridine of melting point 12°-126° C. is obtained.

1. customThen, the ice bath is removed
2. stirringit is stirred for 48 hours at room temperature
3. filtrationThe precipitate is filtered off
4. customthe filtrate is evaporated to dryness
5. additionmixed with water
6. stirringshaken out with ethyl acetate
7. customThe organic phase is dried on sodium sulfate
8. concentrationconcentrated by evaporation
9. customthe residue is chromatographed on silica gel with hexane/0-12% ethyl acetate