反应详情

To a solution of (S)-methyl 4,5,6,7-tetrahydro-1H-indazole-5-carboxylate (500 mg, 2.80 mmol) in methanol (20 mL) were added water (10 mL) and lithium hydroxide hydrate (234 mg, 5.57 mmol) at 0° C. The reaction mixture was stirred at ambient temperature for 2 h and then concentrated to remove most of methanol. The remaining mixture was acidified with diluted aqueous HCl to pH=4 and then concentrated. The residue was dried under vacuum to afford (S)-4,5,6,7-tetrahydro-1H-indazole-5-carboxylic acid (380 mg, 81% yield) as a colorless solid, which was used directly without further purification. (R)-methyl 4,5,6,7-tetrahydro-1H-indazole-5-carboxylate was synthesized in a similar manner.

1. concentrationconcentrated
2. customto remove most of methanol
3. concentrationconcentrated
4. customThe residue was dried under vacuum