Thiophenol → Benzo(b)thiophene-2,3-dione

Participants

Reaction Steps

A solution of oxalyl chloride (73.1 mmol) in ether (14 mL) is added to a solution of thiophenol (45.4 mmol) in ether (20 mL). The mixture is heated to reflux for 90 min, cooled to RT and concentrated in vacuo. The residue is dissolved in DCM (85 mL), cooled to 0° C. and treated portionwise with aluminum chloride (54.5 mmol). The mixture is heated to reflux for 30 min, cooled to RT and poured with stirring into ice-water. The layers are separated and the organic layer is washed with aqueous NaHCO3 solution, water and brine. After drying over MgSO4 the solvents are removed in vacuo and the residue is purified by flash chromatography (gradient: EtOAc/heptane 1/9 to 1/1) to give the desired product. 1H-NMR (CDCl3): δ=7.37 (t, J=7.62 Hz, 1H); 7.42 (d, J=7.62 Hz, 1H); 7.68 (t, J=7.62 Hz, 1H); 7.82 (d, J=7.62 Hz, 1H).

Provenance & Evidence