反应详情

温度

-15 °C

To a stirring solution of 4-(2-methyl-imidazol-1-yl)-benzoic acid methyl ester (250 mg) in MeOH (2 mL) add 10 M NaOH aqueous solution (2.3 mL) and stir the reaction at rt for 20 h. Dilute with water (25 mL) and cool to −15° C. Quench with careful dropwise addition of conc. HCl (2.2 mL) over 5 min to a final pH of 1-2. Wash the suspension with EtOAc (50 mL). Concentrate the aqueous layer to a solid, and further dry in vacuo under P2O5 to remove all moisture. Triturate the solid in MeOH and filter to remove inorganic salts, washing with MeOH. Concentrate the filtrate, triturate the residue in EtOAc/hexane, and filter, washing with hexane. Suspend the solid in 10% MeOH/EtOAc (20 mL) and stir/sonicate. Syringe filter the suspension to remove inorganics solids, concentrate the organic to a solid residue, and repeat this procedure. Triturate the organic residue in EtOAc/hexane and filter/dry the solid to afford the desired product 4-(2-methyl-imidazol-1-yl)-benzoic acid as a solid in 93% yield (238 mg, 1.06 mmol).

1. customthe reaction at rt for 20 h
2. customQuench with careful dropwise addition of conc. HCl (2.2 mL) over 5 min to a final pH of 1-2
3. washWash the suspension with EtOAc (50 mL)
4. concentrationConcentrate the aqueous layer to a solid
5. customfurther dry in vacuo under P2O5
6. customto remove all moisture
7. customTriturate the solid in MeOH
8. filtrationfilter
9. customto remove inorganic salts
10. washwashing with MeOH
11. concentrationConcentrate the filtrate
12. customtriturate the residue in EtOAc/hexane
13. filtrationfilter
14. washwashing with hexane
15. customstir/sonicate
16. filtrationSyringe filter the suspension
17. customto remove inorganics solids
18. concentrationconcentrate the organic to a solid residue
19. customTriturate the organic residue in EtOAc/hexane
20. customfilter/dry the solid