Synthesis
GENERAL STEPS: In a typical reaction, 5.0 mg of Pd-gCN catalyst (containing 5.0 wt% Pd) was mixed with 1.0 mM 1-(4-nitrophenyl)-1H-pyrazole in ethanol (2 mL) and 60% hydrazine hydrate solution (2 mM, 1.2 equiv, 0.07 mL). The mixture was placed in a 10 mL round-bottomed flask and reacted at reflux temperature (70°C) for 4 hours, followed by cooling to room temperature. After completion of the reaction, the reaction mixture was filtered and the filtrate was purified by silica gel column chromatography to afford 4-(1H-pyrazol-1-yl)aniline (1-(4-aminophenyl)pyrazole). For dinitroaromatic substrates, 4.0 mM (2.4 eq., 0.14 mL) of 60% hydrazine hydrate solution is required.
References
[1] Chemical and Pharmaceutical Bulletin, 2000, vol. 48, # 12, p. 1935 - 1946
[2] Applied Catalysis A: General, 2016, vol. 523, p. 31 - 38
[3] Patent: EP3159340, 2017, A1. Location in patent: Paragraph 0086; 0091
[4] Patent: US2015/336982, 2015, A1. Location in patent: Paragraph 0165; 0167
[5] Patent: CN105418590, 2016, A. Location in patent: Paragraph 0152; 0153; 0154
