Citric Acid → 6-(2-carboxyphenyl)methoxy-5,6-dihydro-2-(2-phenylethyl)-4H-imidazo[4,5,1-ij]quinoline

Participants

Reaction Steps

Ethanol (4 mL) was added to 0.62 g of the 5,6-dihydro-6-(2-methoxycarbonylphenyl)methoxy-2-(2-phenylethyl)-4H-imidazo[4,5,1-ij]quinoline obtained in Example 19; to the solution, another solution having potassium hydroxide (0.19 g) dissolved in water (0.4 mL) was added and the mixture was heated under reflux for 1 hr. After standing to cool, the reaction solution was poured into water and its pH was adjusted to 4-5 using 10% aqueous citric acid; after 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: ethyl acetate) to yield the titled compound as pale yellow crystals (0.37 g).

Provenance & Evidence