Methanesulfonic Acid → (2E)-3-[5-(4-fluorophenyl)-1-methyl-1H-pyrazol-4-yl]-N-{4-[(5-methyl-1,3,4-oxadiazol-2-yl)methyl]phenyl}acrylamide

Participants

Reaction Steps

A mixture of (2E)-3-[5-(4-fluorophenyl)-1-methyl-1H-pyrazol-4-yl]-N-[4-(2-hydrazino-2-oxoethyl)phenyl]acrylamide (0.50 g), triethyl orthoacetate (0.63 g), methanesulfonic acid (0.025 g), and tetrahydrofuran (10 mL) was heated under reflux for 1 hr. The reaction mixture was diluted with ethyl acetate, washed successively with saturated aqueous sodium hydrogen carbonate and saturated brine, dried over anhydrous magnesium sulfate and concentrated. The residue was subjected to silica gel column chromatography to give (2E)-3-[5-(4-fluorophenyl)-1-methyl-1H-pyrazol-4-yl]-N-{4-[(5-methyl-1,3,4-oxadiazol-2-yl) methyl]phenyl}acrylamide as pale-yellow crystals (0.25 g, yield 46%) from a fraction eluted with ethyl acetate-methanol (100:0-20:1, v/v). Recrystallization thereof from ethyl acetate-hexane gave pale-yellow prism crystals. melting point: 151-152° C.

Provenance & Evidence