Synthesis
General procedure for the synthesis of 2-methyl-6-amino-2H-indazole from 2-methyl-6-nitro-2H-indazole: 10% palladium-carbon catalyst (51.7% in water, 1 g) was added to a solution of 2-methyl-6-nitro-2H-indazole (7.50 g, 40 mmol) in ethanol (150 ml). The reaction mixture was placed under hydrogen atmosphere and stirred at room temperature for 12 hours. After completion of the reaction, the catalyst was removed by filtration and the catalyst residue was washed with ethanol. The filtrate and washings were combined and the solvent was removed by distillation under reduced pressure to afford the target product 2-methyl-6-amino-2H-indazole as a light beige solid (6.05 g, 95.0% yield).
References
[1] Bioorganic and Medicinal Chemistry Letters, 2014, vol. 24, # 4, p. 1108 - 1110
[2] Chemistry of Heterocyclic Compounds (New York, NY, United States), 1988, p. 403 - 409
[3] Khimiya Geterotsiklicheskikh Soedinenii, 1988, vol. 24, # 4, p. 491 - 498
[4] Journal of Chemical Research, Miniprint, 1990, # 11, p. 2601 - 2615
[5] Heterocycles, 1995, vol. 41, # 3, p. 487 - 496
