2-Aminopyridine → 2-(3-bromophenyl)imidazo[1,2-a]pyridine

Participants

Reaction Steps

Dissolving 10 g (50 mmol) of 3′-bromoacetophenone into 20 milliliter of acetic acid and adding 7.0 g (44 mmol) of bromine at the temperature of about 5 to 10° C., stirred at the temperature of about 5 to 10° C. for 4 hours until the color of bromine disappeared. After completion of the reaction, adding water and an extraction was carried out using dichloro-methane. Further, washing with water, dried with the use of sodium sulfate. The solvent was removed by distillation and the resultant crude 2,3′-dibromo acetophenone was dissolved into 30 milliliter of ethanol, adding 5.0 g (53 mmol) of 2-aminopyridine and 7.0 g of sodium hydrogen carbonate, the resultant suspension was refluxed under heating for 8 hours. After completion of the reaction, separation with filtration was carried out and resultant crystals were washed with water and methanol, thereby obtaining 3.5 g of 2-(3-bromo-phenyl)-imidazo [1,2-a] pyridine (yield: 26%).

Provenance & Evidence