Sodium Hydroxide → 3,5-dimethyl-4-(4-methylpiperazine-1-carbonyl)-1H-pyrrole-2-carbaldehyde

Participants

Reaction Steps

To a mixture of 5-formyl-2,4-dimethyl-1H-pyrrole-3-carboxylic acid (1.67 g, 10 mmol) in dimethylformamide (10 mL) was added benzotriazol-1-yloxytris(dimethylamino)-phosphonium hexafluorophosphate (BOP reagent, 6 g, 13.5 mmol) followed by 3 mL of diisopropylethylamine. After stirring for 5 minutes, 2 mL of 1-methylpiperazine was added and the mixture was stirred at room temperature for 24 hours. To the reaction was then added 25 mL of 1N sodium hydroxide and 25 mL of brine. After stirring for 30 minutes, the reaction mixture was poured into water (100 mL) and extracted (3×200 mL) with 10% of methanol in dichloromethane. The organic layers were combined, dried over anhydrous sodium sulfate and evaporated on a rotary evaporator. The residue which remained was purified by chromatography(silica gel column, 5%-10% of methanol in dichloromethane) to give 1 g (40%) of 3,5-dimethyl-4-(4-methyl-piperazine-1-carbonyl)-1H-pyrrole-2-carboxaldehyde.

Provenance & Evidence