1,1'-Carbonyldiimidazole → 1-(5-Bromonicotinoyl)-3-phenyl-2-pyrazoline

Participants

Reaction Steps

1,1′-Carbonyldiimidazole (1.7 g) was added to a solution of 5-bromonicotinic acid (2 g) dissolved in DMF (20 ml), at room temperature. The mixture was stirred for 1 hour in a nitrogen atmosphere. To the reaction mixture was dropwise added a solution of 3-phenyl-2-pyrazoline (5.7 g) dissolved in DMF (15 ml), with ice-cooling. The mixture was stirred at room temperature for 12 hours. The reaction mixture was concentrated. The residue was dissolved in chloroform. The solution was washed with ice water, dried over anhydrous sodium sulfate, and concentrated. The organic layer was purified by silica gel column chromatography (methanol chloroform=1/100) to obtain 1.4 g of a title compound (yield: 41%).

Provenance & Evidence