Selenium Dioxide → HCID 21034920, compound

Participants

Reaction Steps

The above 1-(2-fluoro-5-methoxybenzyl)-4-ethoxycarbonyl-6,7-dimethoxyisoquinoline was dissolved in ethyl acetate (25 ml) and selenium dioxide was added (723 mg). The mixture was refluxed for 1 hr until all starting material was consumed. The solution was filtered through a layer of Celite and the filtrate was concentrated. The residue was purified through a flash column chromatography using hexane and ethyl acetate (3/1 ratio) to give 1-(2-fluoro-5-methoxybenzoyl-6,7-dimethoxyisoquinoline-4-caboxylic acid ethyl ester (1.28 g). This ester (200 mg, 0.48 mmol) was suspended in 10 ml of methanol and 1N sodium hydroxide solution (2.0 ml) was added. The mixture was refluxed for 30 minutes and the solution was loaded to a preparative HPLC for purification to give 1-(2-Fluoro-5-methoxy-benzoyl)-6,7-dimethoxy-isoquinoline-4-carboxylic acid (138 mg). ES-MS calcd for C20H16FNO6 (m/e) 385.36, obsd 386.2 (M+H).

Provenance & Evidence