2,4,5-Trimethoxybenzaldehyde → HCID 178493432, compound

Participants

Reaction Steps

To a clear light brown solution of 2,4,5-trimethoxybenzaldehyde (600 mg, 3.06 mmol) and 5-amino-1H-pyrazole-4-carbonitrile (331 mg, 3.06 mmol) in methanol (10 mL) in a 20 mL vial were added cyclopentyl isonitrile (294 mg, 342 μL, 3.06 mmol) and perchloric acid (61.4 mg, 54.9 μL, 0.612 mmol) at RT under nitrogen atmosphere. Then, the nitrogen line was disconnected and the resulting dark brown solution slowly became a suspension within few hours which was then stirred for 15 h at RT. The off-white solids were collected by filtration and washed with methanol and the solids were not the desired product. The filtrate was removed under vacuum and the resulting residue was purified using an ISCO (120 g) column chromatography eluting with 0-60% ethyl acetate in hexanes. The desired fractions were combined and the solvent was removed under vacuum to isolate 165 mg (14% yield) of 3-(cyclopentylamino)-2-(2,4,5-trimethoxyphenyl)-1H-imidazo[1,2-b]pyrazole-7-carbonitrile as a dark brown solid. LC/MS calcd. for C20H23N5O3 (m/e) 381.434, obsd. 382.1 (M+H, ES+).

Provenance & Evidence