反应详情

温度

105 °C

A mixture of 2,5-dibromobenzoic acid (1244 g, 4.44 mol), 5-hydroxy-2-chloropyridine (663.3 g, 5.12 mol) and cesium carbonate (2893.3 g, 8.88 mol) was stirred for 20 minutes under a nitrogen atmosphere. To this slurry were added copper (I) trifloromethanesulfonate toluene complex (59.7 g, 0.115 mol), toluene (9 L) and EtOAc (39 mL). The resulting suspension was heated to 105° C. and stirred for 2 h before being cooled to RT. The toluene was decanted, and water (8 L) and EtOAc (8 L) were added. The resulting mixture was stirred until the solid was completely dissolved. The EtOAc layer was separated and the pH of the aqueous layer was adjusted to pH 2˜3 with 6N HCl. The aqueous layer was extracted with EtOAc (3×5 L). The combined organic layers were dried over Na2SO4, filtered and concentrated to give 1.28 Kg of 5-bromo-2-(6-chloropyridin-3-yloxy)benzoic acid as brown solid. This material was used in next step without further purification.

1. stirringstirred for 2 h
2. temperaturebefore being cooled to RT
3. customThe toluene was decanted
4. additionwater (8 L) and EtOAc (8 L) were added
5. stirringThe resulting mixture was stirred until the solid
6. dissolutionwas completely dissolved
7. customThe EtOAc layer was separated
8. extractionThe aqueous layer was extracted with EtOAc (3×5 L)
9. dry with materialThe combined organic layers were dried over Na2SO4
10. filtrationfiltered
11. concentrationconcentrated