反应详情

Sodium hydroxide (40 mL, 6.25 M solution) was added to a stirred solution of 4,6-dichloronicotinic acid ethyl ester (22) (25.95 g, 118 mmol) in 4:1:1 THF/MeOH/water (600 mL). After 30 minutes, the reaction mixture was acidified to pH 2 with concentrated HCl, diluted with 1:1 EtOAc/Et2O and washed with water and brine. The organic layer was dried (Na2SO4) and concentrated. The resulting off-white solid was twice concentrated from toluene to give the desired product (23) as a white solid (21.73 g, 96%).

1. washwashed with water and brine
2. dry with materialThe organic layer was dried (Na2SO4)
3. concentrationconcentrated
4. concentrationThe resulting off-white solid was twice concentrated from toluene