反应详情

The procedure is that of Evans, J. Chem. Soc. (1956), pages 4691-4693. Dimethylformamide (15 mL) is added dropwise to a stirred solution of Grignard reagent prepared from 4.8 g of magnesium and 18.3 g of 4-bromobenzocyclobutene in 40 mL of tetrahydrofuran at 0° C. under a nitrogen atmosphere. The resulting mixture is warmed slowly to room temperature and poured into 100 mL of saturated ammonium chloride solution. The mixture is extracted with ethyl acetate and the organic extract is washed with water and brine and then dried over anhydrous magnesium sulfate. After removing solvent, the product is distilled under reduced pressure to give 11.9 g (90%) of 4-formylbenzocyclobutene, b 90° C./3.5 mm.

1. extractionThe mixture is extracted with ethyl acetate
2. extractionthe organic extract
3. washis washed with water and brine
4. dry with materialdried over anhydrous magnesium sulfate
5. customAfter removing solvent
6. distillationthe product is distilled under reduced pressure