Hydrochloric Acid → 7-benzyloxy-2-ethoxymethyl-1H-imidazo[4,5-c]quinolin-1-amine

Participants

Reaction Conditions

Reaction Steps

A suspension of tert-butyl (7-benzyloxy-2-ethoxymethyl-1H-imidazo[4,5-c]quinolin-1-yl)carbamate (14.4 g, 32.1 mmol) in 100 mL of ethanol was treated with HCl in ethanol (38 mL, 160 mmol, 4.3 M). The mixture was heated to 100° C. under an atmosphere of nitrogen. After 2 h, the reaction mixture was cooled to ambient temperature at which point a solid precipitated from solution. The mixture was diluted with 100 mL of diethyl ether and the solid was triturated for 15 min. The solid was collected by vacuum filtration and washed with several portions of diethyl ether. The solid was dried under vacuum for 2 h. The dry solid was suspended in 150 mL of water and treated with 50% NaOH solution until the pH of the liquid was 12. A brown solid precipitated. The mixture was diluted with 200 mL of CH2Cl2 and stirred until the solid dissolved. The layers were then separated. The aqueous portion was extracted with CH2Cl2 (2×100 mL). The combined organic extracts were washed with brine (100 mL), dried over Na2SO4, filtered and concentrated under reduced pressure to yield 6.91 g of 7-benzyloxy-2-ethoxymethyl-1H-imidazo[4,5-c]quinolin-1-amine as a dark tan solid.

Provenance & Evidence