Boron tribromide → HCID 57515436, compound

Participants

Reaction Conditions

Reaction Steps

A suspension of 4-{[4-amino-2-(2-methoxyethyl)-1H-imidazo[4,5-c]quinolin 1-yl]methyl}tetrahydro-2H-pyran-4-ol (0.95 g, 2.67 mmol) in dichloromethane (15 mL) was cooled to 0° C. Boron tribromide (8 mL, 8.00 mmol) was added and the reaction mixture was allowed to stir overnight while slowly warming to ambient temperature. The reaction mixture was concentrated. The residue was taken up in a mixture of methanol (15 mL) and 6M hydrochloric acid (10 mL) and refluxed for 2.5 hours. The reaction mixture was cooled to ambient temperature and the pH was adjusted to 8 with 2M sodium hydroxide. The mixture was extracted with chloroform (12×20 mL). The combined extracts were dried over magnesium sulfate, filtered, and then concentrated under reduced pressure to provide a yellow solid. This material purified by HPFC eluting with a gradient of 0 to 45% CMA in chloroform to provide an off white solid. The solid was triturated with acetonitrile, isolated by filtration, and dried in a vacuum oven at 140° C. to provide 0.536 g of 4-{[4-amino-2-(2-hydroxyethyl)-1H-imidazo[4,5-c]quinolin-1-yl]methyl}tetrahydro-2H-pyran-4-ol as a white solid, mp 237-238° C. MS (ESI) m/z 343 (M+H)+; Anal. calcd for C18H22N4O3: C, 63.14; H, 6.48; N, 16.36. Found: C, 63.04; H, 6.57; N, 16.19.

Provenance & Evidence