Hydrochloric Acid → 5-amino-1-(4-methoxyphenyl)-3-methyl-1H-pyrazole-4-carbonitrile

Participants

Reaction Conditions

Reaction Steps

To a stirred solution of 2-(1-ethoxyethylidene)malononitrile (1.00 g, 6.66 mmol) in EtOH (8 mL) was added (4-methoxyphenyl)hydrazine (1.29 g, 9.32 mmol). (Prior to use the hydrazine its HCl salt was washed with NaHCO3/CH2Cl2. The organic phase was concentrated and used directly.) The solution was heated to 105° C. in the microwave for 20 min. CH2Cl2 was added and the organic phase was washed with 1M HCl and the organic extract was washed with aqueous NaHCO3. The solution was dried using a phase separator and concentrated under reduced pressure to give 5-amino-1-(4-methoxyphenyl)-3-methyl-1H-pyrazole-4-carbonitrile (1.38 g, 85%) which was used as such in the next step. The procedure was adapted from J. Med. Chem. 2004, 47, 5894-5911.

Provenance & Evidence