Formamidine acetate → HCID 178517944, compound

Participants

Reaction Steps

A mixture of formamidine acetate (12.5 g, 0.12 mol) and 4-amino-1-(2-chlorophenyl)-5-(4-(trifluoromethyl)phenyl)-1H-pyrazole-3-carboxylic acid ethyl ester (4.77 g, 11.6 mmol; prepared using procedures and reagents analogous to those described above in the synthesis of 4-amino-1-(2-chlorophenyl)-5-(4-chlorophenyl)-1H-pyrazole-3-carboxylic acid ethyl ester (I-2A-1a)) in ethanol (400 ml) was heated at reflux for 20 hours. The reaction was then cooled and concentrated in vacuo. The residue was extracted from water, adjusted to pH 3.5 using citric acid, with ethyl acetate, and the combined organic layers were washed with half saturated brine, dried (MgSO4), and concentrated in vacuo. Purification of the residue by silica gel chromatography using 10-50% ethyl acetate in hexanes as eluant afforded compound I-2A-2a (1.03 g, 23%) as a solid: APcl MS (M+1) 389.1; 1H NMR (CD3OD) δ 7.92 (s, 1H), 7.71-7.53 (m, 8H).

Provenance & Evidence