Benzenesulfonyl chloride → methyl [4-amino-1-(2-hydroxy-2-methylpropyl)-1H-imidazo[4,5-c]quinolin-2-yl]carbamate

Participants

Reaction Conditions

Reaction Steps

A suspension of methyl [1-(2-hydroxy-2-methylpropyl)-5-oxido-1H-imidazo[4,5-c]quinolin-2-yl]carbamate (0.80 g, 2.4 mmol) in methanol (10 mL) was stirred vigorously and cooled to 0° C. Concentrated ammonium hydroxide (0.8 mL, 25 mmol) was added followed by benzenesulfonyl chloride (0.9 g, 5 mmol), which was added dropwise. The mixture was stirred for two hours at 0° C. to 5° C. An analysis by LC/MS indicated the reaction was incomplete. Additional benzenesulfonyl chloride (0.9 g) was added, and the reaction mixture was stirred overnight at room temperature. The solvent was removed under reduced pressure, and the residue was purified by automated flash chromatography (40+M silica cartridge, eluting with 0% to 25% CMA in chloroform) followed by recrystallization from ethyl acetate to provide 0.36 g of methyl [4-amino-1-(2-hydroxy-2-methylpropyl)-1H-imidazo[4,5-c]quinolin-2-yl]carbamate as a white solid, mp 255-258° C. (decomposition).

Provenance & Evidence