Formic Acid → HCID 13282176, compound

Participants

Reaction Steps

A mixture of acetic anhydride (200 mL) and 98% formic acid (10 mL) was heated at 50°-60° C. for 15 minutes. After cooling, 2-methyl-2H-benzofuro[3,2-c]pyrazol-3-amine (5.0 g, 27 mmol, described in Example 6) was added. After stirring overnight at room temperature, the mixture was poured on a mixture of ice and water and extracted with methylene chloride. The organic extract was dried and evaporated. The residue was chromatographed through silica gel using 5% EtOH--CH2Cl2 (v/v) and the eluates were evaporated. Trituration of the resulting residue with diethyl ether gave 3.0 g of N-(2-methyl-2H-benzofuro[3,2-c]pyrazol-3-yl)formamide: mp 184°-187° C.; IR (mineral oil) 3190 and 1670 cm-1 ; UV max (MeOH) 269 nm (ε=21100), 222 (19500) and shoulder at 291 and 215; NMR (DMSO-d6) δ3.85 (3H, s), 7.5 (4H, m), 8.4 (1H, s) and 10.4 (1H, br); and Anal. Calcd for C11H9N3O2 : C, 61.39% H, 4.21% N, 19.53% and Found: C, 61.17% H, 4.27% N, 19.37%.

Provenance & Evidence