反应详情

To a solution of 5-nitro-1-trityl-1H-indazole-3-carboxylic acid methyl ester 19AP (12.95 g, 27.96 mmol) in THF (270 ml) and H2O (135 ml) was added LiOH.H2O (2.34 g, 55.92 mmol) at room temperature. After stirring for overnight at room temperature, it was cooled to 0° C. and acidified with slow addition of 1N HCl (55.9 ml, 55.92 mmol). Reaction mixture was concentrated under reduced pressure. Solid was collected by filtration and washed with water to give desired 5-nitro-1-trityl-1H-indazole-3-carboxylic acid 20AP (12.06 g, 96%).

1. temperatureit was cooled to 0° C.
2. customReaction mixture
3. concentrationwas concentrated under reduced pressure
4. filtrationSolid was collected by filtration
5. washwashed with water