Perchloric Acid → HCID 178510453, compound

Participants

Reaction Steps

To a clear colorless solution of 4-bromobenzaldehyde (3.71 g, 20.1 mmol) and 5-amino-1H-pyrazole-4-carbonitrile (2.17 g, 20.1 mmol) in a 350 mL sealed tube in methanol (70 mL) were added cyclopentane isonitrile (1.93 g, 2.24 mL, 20.1 mmol) and perchloric acid (403 mg, 360 μL, 4.01 mmol) at RT under nitrogen atmosphere. Then, the nitrogen line was disconnected and the flask was sealed with a cap. The resulting light yellow solution slowly became a suspension within 5 minutes which was then stirred for 15 h at RT. The off-white solids were collected by filtration and washed with methanol. After air drying, 5.1 g (68.7% yield) of 3-(cyclopentylamino)-2-(4-bromophenyl)-1H-imidazo[1,2-b]pyrazole-7-carbonitrile was isolated as an off-white solid. LC/MS calcd. for C17H16BrN5 (m/e) 370.25, obsd. 372.0 (M+H, ES+).

Provenance & Evidence