反应详情

A mixture of ethyl 2,4-dibromothiazole-5-carboxylate (0.500 g, 1.59 mmol), N-(4-(trimethylstannyl)pyridin-2-yl)acetamide (0.569 g, 1.90 mmol), tetrakis(triphenylphosphine)palladium(0) (91.7 mg, 0.0794 mmol), copper(I) iodide (90.7 mg, 0.476 mmol), and lithium chloride (202 mg, 4.76 mmol) in dioxane (29.1 mL) was degassed with nitrogen and heated at reflux for 1 hr. The reaction was cooled and concentrated in vacuo. The residue was purified by silica gel chromatography (ethyl acetate/hexane=0/100→50/50) to give 312 mg of the title compound. (44% yield). LC/MS (FA) ES+ 370, 372. 1H NMR (400 MHz, CDCl3) δ: 8.71 (s, 1H), 8.39 (d, 1H, J=5.2 Hz), 8.25 (bs, 1H), 7.68 (dd, 1H, J=5.2, 1.6 Hz), 4.41 (q, 2H, J=7.2 Hz), 2.26 (s, 3H), 1.41 (t, 3H, J=7.2 Hz).

1. customwas degassed with nitrogen
2. temperatureheated
3. temperatureat reflux for 1 hr
4. temperatureThe reaction was cooled
5. concentrationconcentrated in vacuo
6. customThe residue was purified by silica gel chromatography (ethyl acetate/hexane=0/100→50/50)