反应详情

n-Butyllithium (1.2 mL 1.92 mmol, 1.6 M/hexanes) was added to a −78° C. solution of 1,4-dibromobenzene (489 mg, 2.07 mmol) in THF (4.2 mL). After 30 min., a solution of cyclobutanone (141 mg, 2.01 mmol) in 1 mL THF was added by cannula, rinsing with 0.5 mL THF. The reaction was allowed to warm to room temperature and after 2 h, saturated NH4Cl solution was added. The resulting mixture was extracted with ethyl acetate (3×30 mL) and the combined ethyl acetate solution was washed with brine. The solution was then dried (Na2SO4), filtered and evaporated. Purification by flash chromatography on silica gel (5%→10% ethyl acetate/hexanes) gave 3-1 (235 mg, 54%).

1. washrinsing with 0.5 mL THF
2. additionsaturated NH4Cl solution was added
3. extractionThe resulting mixture was extracted with ethyl acetate (3×30 mL)
4. washthe combined ethyl acetate solution was washed with brine
5. dry with materialThe solution was then dried (Na2SO4)
6. filtrationfiltered
7. customevaporated
8. customPurification by flash chromatography on silica gel (5%→10% ethyl acetate/hexanes)