Lithium Hydroxide → HCID 23369864, compound

Participants

Reaction Steps

Ethyl 3-cyano-9-hydroxy-4-(3-nitrophenyl)-2-(1-pyrrolyl)-4H-naphtho[1,2-b]pyran-8-carboxylate (1.91 g) was dissolved in THF (10 ml). Water (1 ml) and lithium hydroxide monohydrate (180 mg) were added and the solution stirred at room temperature for 45 minutes. A further quantity of lithium hydroxide (180 mg) was added and the solution heated under reflux for one hour. The solution was poured into water (100 ml) and glacial acetic acid (50 ml) added. Solid sodium chloride was added until no more would dissolve, then the mixture extracted with ethyl acetate (3×200 ml). The combined organic extracts were dried over magnesium sulphate, then solvent removed under reduced pressure to give a brown-yellow solid. This was triturated with ether (10 ml), the solid collected by filtration and dried to yield 3-cyano-9-hydroxy-4-(3-nitrophenyl)-2-(1-pyrrolyl)-4H -naphtho[1,2-b]pyran-8-carboxylic acid, m.p. >230° C.

Provenance & Evidence