Benzoyl chloride → N1-[4-(4-amino-1H-imidazo[4,5-c]quinolin-1-yl)butyl]benzamide

Participants

Reaction Conditions

Reaction Steps

A suspension of 1-(4-aminobutyl)-1H-imidazo[4,5-c]quinolin-4-amine (2.0 g, 7.8 mmol) in pyridine (1 L) was warmed to 60° C. to dissolve the starting material. The solution was cooled to about 30° C. and then benzoyl chloride (1.1 g, 7.8 mmol) diluted with pyridine (100 mL) was slowly added. After 1 hour analysis by high performance liquid chromatography (HPLC) indicated that some starting material remained. Additional benzoyl chloride (0.3 g) was added and the reaction was warmed to 50° C. overnight. The reaction mixture was concentrated under vacuum. The resulting residue was combined with chloroform (200 mL) and 1% sodium carbonate (200 mL). The organic layer was separated and then concentrated under vacuum. The resulting residue was combined with propyl acetate (30 mL) and heated on a steam bath to dissolve the residue. The solution was allowed to cool. The resulting precipitate was isolated by filtration to provide N1-[4-(4-amino-1H-imidazo[4,5-c]quinolin-1-yl)butyl]benzamide as a solid, m.p. 210-212° C. Analysis: Calculated for C21H21N5O: %C, 70.18; %H, 5.89: %N, 19.48; Found: %C, 69.49; %H, 5.97; %N, 19.64. 1H NMR (500 MHz, DMSO-d6) δ8.48 (t, J=6.0 Hz, 1H), 8.22 (s, 1H), 8.04 (d, J=8.0 Hz, 1H), 7.78 (d, J=8.0 Hz, 2H), 7.61 (d, J=8.0 Hz, 1H), 7.50 (t, J=8.0 Hz, 1H), 7.43 (m, 3H), 7.21 (t, J=8.0 Hz, 1H), 6.62 (broad s, 2H), 4.64 (t, J=7.0 Hz, 2H), 3.30 (q, J=6.0 Hz, 2H), 1.92 (quintet, J=7.0 Hz, 2H), 1.58 (quintet, J=7.0 Hz, 2H); MS (EI) m/e 359.1746 (359.1746 calcd for C21H21N5O).

Provenance & Evidence