Toluene → 1-(4-Ethoxycarbonyl-phenyl)-2-oxo-1,2-dihydro-pyridine-4-carboxylic acid

Participants

Reaction Steps

A mixture of 2-oxo-1,2-dihydro-pyridine-4-carboxylic acid methyl ester (2.00 g), 1.0M tetrabutylammonium hydroxide in H2O (13 ml) and toluene (50 mL) was stirred for 2 hours at ambient temperature. Mixture was concentrated and co-evaporated with toluene (3×100 mL) and dried under high vacuum. To the residue was added 4-Iodo-benzoic acid ethyl ester (2.40 g) and co-evaporated with toluene (2×20 mL). Copper iodide (0.829 g) and DMF (10 mL) were added and reaction mixture heated at 95° C. for 18 hours, protected from light. To the cooled reaction mixture was added 3N ammonium hydroxide and extracted with dichloromethane (4×). Organic layer was dried (MgSO4), concentrated and purified by flash column chromatography (silica gel, 0 to 5% methanol/dichloromethane+1% triethylamine) to give 1-(4-Ethoxycarbonyl-phenyl)-2-oxo-1,2-dihydro-pyridine-4-carboxylic acid (1.155 g) as the triethylammonium salt: LCMS-ESI−: calc'd for C15H12NO5: 286.27 (M−H+). Found: 286.1 (M−H+).

Provenance & Evidence