Iodine → 1-Iodo-5-(5-carboxypentyl)-imidazo[1,5-a]pyridine

Participants

Reaction Steps

Iodine crystals (1.9 g) are added to a well-stirred solution of 1.16 g of 5-(5-carboxypentyl)-imidazo[1,5-a]pyridine and 1.68 g of sodium bicarbonate in 10 ml of water and 1 ml of ethanol. Additional 4 ml of ethanol are added to dissolve the bulk of the iodine and stirring is continued for 45 minutes. The reaction mixture is diluted with 125 ml of water and extracted twice with methylene chloride at pH 8 (NaHCO3 added if necessary). The aqueous phase is concentrated in vacuo, charcoaled and adjusted to pH 4.5 with 2 N HCl. The precipitate is collected, dried and recrystallized from methanol/ether to give 1-iodo-5-(5-carboxypentyl)-imidazo[1,5-a]pyridine melting at 163°-165°.

Provenance & Evidence