反应详情

To a solution of 3,4-dichloro-N-methoxy-N-methyl-1,2-thiazole-5-carboxamide (3.80 g, 15.7 mmol) in tetrahydrofuran (130 mL) at −5° C. was added dropwise a solution of iodo(3-thienyl)magnesium in tetrahydrofuran (0.3 M, 158 mL, 47.4 mmol). After stirring at room temperature for 72 h, the reaction was worked-up by the addition of aq. HCl (1 M) until pH<7. After removal of the tetrahydrofuran in vacuo, the aqueous phase was extracted with ethyl acetate (3×50 mL). The organic layers were combined, dried over MgSO4 and concentrated in vacuo. The residue was purified on silica gel to afford (3,4-dichloro-1,2-thiazol-5-yl)(3-thienyl)methanone [3.00 g, yield 65%; HPLC/MS: m/z=264 (M+H); log P(HCOOH)=3.31].

1. customAfter removal of the tetrahydrofuran in vacuo
2. extractionthe aqueous phase was extracted with ethyl acetate (3×50 mL)
3. dry with materialdried over MgSO4
4. concentrationconcentrated in vacuo
5. customThe residue was purified on silica gel