N-bromobutanimide → Methyl 4-bromo-5-methoxythiophene-2-carboxylate

Participants

Reaction Steps

NBS (903 mg, 5.07 mmol) was added in portions to a 5 mL sealed tube reactor containing methyl 5-(methyloxy)-2-thiophenecarboxylate (0.73 g, 4.23 mmol) in N,N-Dimethylformamide (DMF) (20 mL) at room temperature and the reaction stirred for 1 hour. Additional NBS (249 mg) was added and after 1 h at room temperature the product was partitioned between CHCl3 and H2O. The organic layer was dried with Na2SO4, adsorbed onto silica and purified via column chromatography (0-25% EtOAc/Hexanes) affording the title compound (825 mg, 3.19 mmol, 75%): LC-MS (ES) m/z=252 (M+H)+.

Provenance & Evidence