反应详情

温度

0 °C

To a mixture of ethyl 4-chloro-5-formyl-6,7-dihydro-3-methylthiobenzo[c]thiophene-1-carboxylate (3.00 g), triethylamine (1.44 g) and pyridine (25 ml), ethyl thioglycolate (1.37 g) was added at 0° C., followed by stirring at 0° C. for 1.5 hours. The reaction mixture was concentrated under reduced pressure; the residue was poured over water and extracted with ethyl acetate. The organic layer was washed with 1 N hydrochloric acid and water in that order and dried (MgSO4), after which the solvent was distilled off. The residue was subjected to silica gel column chromatography and eluted with ethyl acetate-hexane (1:7 to 1:5, v/v) to yield ethyl 4-ethoxycarbonylmethylthio-5-formyl-6,7-dihydro-3-methylthiobenzo[c]thiophene-1-carboxylate (3.07 g, 81.0%), which was then recrystallized from ethyl acetate-hexane. Yellow prisms. Melting point 102-103° C.

1. additionwas added at 0° C.
2. concentrationThe reaction mixture was concentrated under reduced pressure
3. additionthe residue was poured over water
4. extractionextracted with ethyl acetate
5. washThe organic layer was washed with 1 N hydrochloric acid and water in that order
6. dry with materialdried (MgSO4)
7. distillationafter which the solvent was distilled off
8. washeluted with ethyl acetate-hexane (1:7 to 1:5