反应详情

3-Bromo-4-chlorobenzoic acid ethyl ester (1.05 g, 3.99 mmol) was added in one portion to a solution of diisopropylzinc (10.0 mmol, 1M toluene, Aldrich) in 10 mL of 1,4-dioxane followed by addition of Pd(dppf)2Cl2 (4.0 mmol). The mixture was heated to reflux 3 hours, cooled to ambient temperature and stirred overnight. The mixture was quenched with 1N aqueous HCl, diluted with ethyl acetate, and filtered through celite. The separated organic layer was washed sequentially with 1N aqueous HCl, brine, dried (Na2SO4), filtered and concentrated under reduced pressure. The residue was purified by chromatography eluting with 4% ethyl acetate/hexanes to provide the title compound. 1H NMR (DMSO-d6) δ 7.92 (d, 1H), 7.78 (dd, 1H), 7.58 (d, 1H), 4.32 (q, 2H), 3.35 (sept, 1H), 1.32 (t, 3H), 1.24 (d, 6H).

1. temperatureThe mixture was heated
2. temperatureto reflux 3 hours
3. customThe mixture was quenched with 1N aqueous HCl
4. additiondiluted with ethyl acetate
5. filtrationfiltered through celite
6. washThe separated organic layer was washed sequentially with 1N aqueous HCl, brine
7. dry with materialdried (Na2SO4)
8. filtrationfiltered
9. concentrationconcentrated under reduced pressure
10. customThe residue was purified by chromatography
11. washeluting with 4% ethyl acetate/hexanes