反应详情

A suspension of 4-bromothiazole (1.13 g, 6.89 mmol), 4-methoxycarbonylphenylboronic acid (1.85 g, 10.3 mmol) and Tetrakis (triphenylphosphine) palladium (0) (0.35 g, 0.30 mmol) in dioxane (45 mL) and 2M Na2CO3 (17.2 mL) is heated to reflux for 18 h. The reaction is allowed to cool and filtered. The filtrate is evaporated in vacuo, and the residue is dissolved in ethyl acetate and washed with water (2×) and brine (2×). The combined organic layers are dried over Na2SO4, and concentrated in vacuo. The crude material is purified by flash chromatography (100% hexanes-40% ethyl acetate/hexanes) to give 4-thiazol-4-yl-benzoic acid methyl ester as a white solid (0.68 g, 45%) MS (ES+) 220.2

1. temperatureis heated
2. temperatureto reflux for 18 h
3. temperatureto cool
4. filtrationfiltered
5. customThe filtrate is evaporated in vacuo
6. dissolutionthe residue is dissolved in ethyl acetate
7. washwashed with water (2×) and brine (2×)
8. dry with materialThe combined organic layers are dried over Na2SO4
9. concentrationconcentrated in vacuo
10. customThe crude material is purified by flash chromatography (100% hexanes-40% ethyl acetate/hexanes)