2,5-Dimethoxytetrahydrofuran → 1-(2-methylpropyl)-8-(1-pyrrolyl)-1H-imidazo[4,5-c]quinolin-4-amine

Participants

Reaction Steps

2,5-Dimethoxytetrahydrofuran (1.6 mL of 95%, 12 mmol) was added to a suspension of 8-amino-1-(2-methylpropyl)-1H-imidazo[4,5-c]quinolin-4-amine (3.0 g, 12 mmol) in acetic acid (60 mL), and the reaction was heated at reflux for one hour. The resulting dark brown solution was concentrated under reduced pressure, and the residue was mixed with water. The resulting mixture was made basic with the addition of ammonium hydroxide and stirred for 30 minutes. The resulting precipitate was isolated by filtration, washed with water, dried, and recrystallized from ethanol (100 mL). The crystals were collected in three crops. The first crop was dried for a day in a vacuum oven at 100° C. to provide 2.1 g of 1-(2-methylpropyl)-8-(1-pyrrolyl)-1H-imidazo[4,5-c]quinolin-4-amine as a solid, mp 227.5–231.5° C.

Provenance & Evidence