Nitromethane → 5-amino-4-[(E)-2-nitroethenyl]-1-(2-triphenylmethyloxyethyl)-1H-pyrazole

Participants

Reaction Steps

A solution of 5-amino-1-(2-triphenylmethyloxyethyl)-1H-pyrazole-4-carbaldehyde (15 g) and ammonium acetate (4.07 g) in nitromethane (300 ml) was refluxed for 6.5 hours. The reaction mixture was evaporated under reduced pressure and extracted with dichloromethane. The extract was dried over anhydrous magnesium sulfate, filtered, and evaporated in vacuo to give 5-amino-4—[(E)-2-nitroethenyl]-1-(2-triphenylmethyloxyethyl)-1H-pyrazole (4.46 g). 1H-NMR(DMSO-d6) δ3.15 (2H, t, J=4.9 Hz), 4.16 (2H, t, J=4.9 Hz), 6.96 (2H, s), 7.1–7.3 (15H, m), 7.75 (1H, d, J=12.9 Hz), 7.83 (1H, s), 8.27 (1H, d, J=12.9 Hz)

Provenance & Evidence