反应详情

Lithiumhydroxide monohydrate (2.41 g, 57 mmol) was added to a solution of 6-chloro-5-(4-chloro-phenyl)-nicotinic acid methyl ester (8.1 g, 29 mmol) in tetrahydrofuran (120 mL) and water (34 mL) under nitrogen at room temperature. The reaction mixture was stirred for 20 h at room temperature, poured onto ice/water (200 g), acidified with 1 N HCl (120 mL) and the whole was extracted with ethyl acetate (250 mL). The water phase was extracted twice with ethylacetate (2×200 mL), organic phases were combined, dried over MgSO4 and concentrated in vacuo. 6-chloro-5-(4-chloro-phenyl)-nicotinic acid was isolated as a colorless solid and used without further purification; 7.30 g (94% yield). m/z (ISP−): 266.1 (M−H).

1. additionpoured onto ice/water (200 g)
2. extractionthe whole was extracted with ethyl acetate (250 mL)
3. extractionThe water phase was extracted twice with ethylacetate (2×200 mL), organic phases
4. dry with materialdried over MgSO4
5. concentrationconcentrated in vacuo