反应详情

Imidazole (710 mg, 10.4 mmol, 2 Eq.) and 2-Chloro-3-oxo-2,3-dihydrothiophene-2-carboxylic acid methyl ester (1.0 g, 5.19 mmol, 1.0 Eq.) were dissolved in anhydrous DCM (25 mL) and stirred at ambient temperature for 18 hours. The crude reaction mixture was partitioned between EtOAc (50 mL) and brine (50 mL), The aqueous phase was extracted with EtOAc (3×20 mL) and the combined organice extracts washed with brine (1×10 mL), dried (Na2SO4) and concentrated in vacuo. The residue was purifed by column chromatography (5% MeOH/DCM) and recrystalised from EtOAc/hexane to give the sub-title compound as a yellow powder (692 mg, 3.09 mmol 59%); 1H NMR (400 MHz, d-6 DMSO) δ 3.77 (3H, s), 7.02 (1H, s), 7.14 (1H, d), 7.74 (1H, d), 8.28 (1H, d), 10.82 (1H, br s).

1. customThe crude reaction mixture
2. customwas partitioned between EtOAc (50 mL) and brine (50 mL)
3. extractionThe aqueous phase was extracted with EtOAc (3×20 mL)
4. washthe combined organice extracts washed with brine (1×10 mL)
5. dry with materialdried (Na2SO4)
6. concentrationconcentrated in vacuo
7. customrecrystalised from EtOAc/hexane