Triethylamine → HCID 16224282, compound

Participants

Reaction Steps

Triethylamine (3.86 mL, 10 eq) was added to a chilled (ice/water bath) suspension of N-[4-(4-amino-2-ethyl-1H-imidazo[4,5-c]quinolin-1-yl)butyl]methanesulfonamide (1.0 g, 1 eq) in N,N-dimethylformamide (DMF) (10 mL). Ethyl chloroformate (1.5 g, 5 eq) was added dropwise to give a clear solution. The reaction mixture was allowed to come to ambient temperature with stirring for 2 hours. Additional triethylamine (3.86 mL, 10 eq) and ethyl chloroformate (3.86 mL, 10 eq) were added and the reaction mixture was stirred overnight. The reaction mixture was poured onto crushed ice and then extracted with dichloromethane (50 mL). The organic layer was washed sequentially with water (2×50 mL), 4% sodium carbonate (50 mL), water (50 mL), and brine (50 mL) and then concentrated under reduced pressure. The residue was purified by automated flash chromatography (silica gel eluted with a linear gradient of 0-25% CMA in chloroform, 2500 mL) followed by recrystallization from acetonitrile to provide 0.815 g of ethyl 2-ethyl-1-{4-[(methylsulfonyl)amino]butyl}-1H-imidazo[4,5-c]quinolin-4-ylcarbamate as a white crystalline solid, mp 185-187° C. Anal calcd for C20H27N5O4S: C, 55.41; H, 6.28; N, 16.15. Found: C, 55.30; H, 6.29; N, 16.24.

Provenance & Evidence