反应详情

温度

105 °C

A solution of 1-(4-methoxybenzyl)-4-nitro-1H-pyrazole (1031 mg, 4.42 mmol) in EtOH (25 mL) and sat. aq. NH4Cl (15 mL) in a sealed tube (125 mL) was treated with iron (1234 mg, 22.10 mmol, Aldrich, St. Louis, Mo.). The mixture was stirred at 105° C. for 1 h, then cooled to room temperature. The mixture was diluted with EtOAc (200 mL) and filtered through a plug of Celite® (diatomaceous earth). The filtrate was separated and the organic layer was dried (MgSO4), filtered and concentrated in vacuo. The residue was filtered through a plug of silica gel (eluting with DCM:EtOAc:MeOH=25:25:1) to give 1-(4-methoxybenzyl)-1H-pyrazol-4-amine (560 mg, 2.76 mmol, 62.3% yield) as a brown solid. m/z (ESI, positive ion) 204 (M+H)+.

1. temperaturecooled to room temperature
2. filtrationfiltered through a plug of Celite® (diatomaceous earth)
3. customThe filtrate was separated
4. dry with materialthe organic layer was dried (MgSO4)
5. filtrationfiltered
6. concentrationconcentrated in vacuo
7. filtrationThe residue was filtered through a plug of silica gel (eluting with DCM:EtOAc:MeOH=25:25:1)