Potassium Carbonate → Methyl 5-methyl-1-benzofuran-2-carboxylate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A stirring suspension of 5-methylsalicylaldehyde (1.0 mg, 7.5 mmol), K2CO3 (1.55 g, 11.0 mmol), and Bu4NBr (322 mg, 1 mmol) in toluene (30 ml) was treated with dimethylbromomalo-nate (1.06 ml, 8.0 mmol). The suspension was heated to reflux with a Dean-Stark trap for 20 h. The brown suspension was cooled to 25° C. and concentrated in vacuo. The residue was taken in DCM and filtered. The filtrate was washed with H2O, 1N NaOH and brine. The organic layer was dried over magnesium sulfate, filtered and concentrated. The crude residue was purified by column chromatography (10% ethyl acetate/hexane) to afford the title compound 583 (600 mg, 42% yield). LRMS: 190.2 (Calc.); 191.1 (found).

Herkunft & Nachweise