Methanol → 1-ethoxy-1H-imidazo[4,5-c]quinolin-4-amine

Participants

Reaction Conditions

Reaction Steps

A solution of 1-ethoxy-5-oxido-1H-imidazo[4,5-c]quinoline (2.4 g, 10.5 mmol) in dichloromethane (75 mL) was cooled to 0° C., and trichloroacetyl isocyanate (1.9 mL, 16 mmol) was added. The reaction was stirred for ten minutes at 0° C. and then stirred overnight at room temperature. Methanol (15 mL) was added, and the mixture was stirred for 15 minutes and concentrated under reduced pressure. The residue was dissolved in methanol (15 mL), and sodium methoxide (0.5 mL of a 25% w/w solution in methanol) was added. The mixture was stirred at room temperature for three hours and concentrated under reduced pressure. The residue was stirred with methanol (15 mL) and water (15 mL), and a solid formed. The solid was collected by filtration, recrystallized from methanol/water, and purified by column chromatography on silica gel (eluting with 5% methanol in dichloromethane containing 2 mL of aqueous ammonium hydroxide per liter of eluent). The resulting solid was recrystallized from methanol/water and dried overnight under vacuum to provide 0.54 g of 1-ethoxy-1H-imidazo[4,5-c]quinolin-4-amine as brown crystals, mp 179-181° C.

Provenance & Evidence