1,3-Cyclohexanedione → HCID 178470352, compound

Participants

Reaction Steps

A suspension of 462.5 mg (3.0 mmol) of 3-amino-2-ethoxycarbonylpyrrole and 822.9 mg (3.0 mmol) of 5-(5-methoxy-1H-benzimidazol-2-ylsulfanyl)-furan-2-carbaldehyde (obtained from step 1) in 15 mL of ethanol under argon is stirred at room temperature for 1 hour. 1,3-Cyclohexanedione (336.4 mg, 3.0 mmol) is then added and the reaction mixture is heated at reflux temperature for 16 h. The mixture is then cooled to 0° C., filtered and the precipitate is washed with diisopropyl ether. The solid is then purified by chromatography on a prepacked 90 g 15-40 μm silica gel cartridge (eluting solvent: ethyl acetate/methanol/trifluoroacetic acid 98/1/1 v/v/v; rate: 40 mL/min). The fractions containing the desired product are combined and concentrated to dryness under reduced pressure. The residue is purified by chromatography on a prepacked 90 g 15-40 μm silica gel cartridge (eluting solvent: ethyl acetate/cyclohexane from 50/50 to 75/25 v/v; rate: 40 mL/min). The fractions containing the desired product are combined and concentrated to dryness under reduced pressure. 330 mg of 9-[5-(5-methoxy-1H-benzimidazol-2-ylsulfanyl)-furan-2-yl]-8-oxo-4,5,6,7,8,9-hexahydro-2H-pyrrolo[3,4-b]quinoline-3-carboxylic acid ethyl ester are obtained as a yellow powder. mp: 140° C. LCMS: m/z 505: [M+H]+ (base peak); m/z 503: [M−H]− (base peak).

Provenance & Evidence