Acetone → 5,6-dihydro-2-(2-phenylethyl)-6-(2-propylamino)-4H-imidazo[4,5,1-ij]quinoline

Participants

Reaction Steps

A portion (1.0 g) of 5,6-dihydro-2-(2-phenylethyl)-4H-imidazo[4,5,1-ij]quinolin-6-amine obtained in step 2 of Example 17 was dissolved in methanol (10 mL) and, following the addition of acetone (0.53 mL) and 10% HCl-methanol solution (0.1 mL), the mixture was stirred at room temperature for 4 days. The reaction solution was cooled with ice and, following the addition of sodium cyanoborohydride (0.23 g), the mixture was stirred at room temperature for 24 hrs. The reaction mixture was concentrated and, to the residue was added water followed by extraction with ethyl acetate; the organic layer was washed with saturated brine and dried over anhydrous sodium sulfate. The solvent was removed under reduced pressure and the residue was purified by silica gel column chromatography (eluent: dichloromethane/methanol) to yield the titled compound as pale yellow crystals (0.80 g).

Provenance & Evidence