反应详情

A solution of n-butyllithium in hexanes (1.65M, 4.92 mL) was added dropwise to a solution of 1,4-dibromobenzene (2.05 g) in THF (25 mL) dropwise over the course of 30 min at −78° C. The resulting mixture was stirred at the same temperature for 1 h. To the mixture was added a solution of 2-methyl-N-oxetan-3-ylidenepropane-2-sulfinamide (1.02 g) in THF (5 mL) dropwise over the course of 30 min at −78° C. The reaction mixture was stirred for an additional 30 min. at −78° C. then allowed to warm to room temperature. After being stirred for 1 h at room temperature, the reaction mixture was quenched by addition of saturated ammonium chloride aqueous solution. The aqueous layer was extracted with ethyl acetate. The combined organic layer was washed with saturated sodium bicarbonate solution then brine. The organics were dried over anhydrous sodium sulfate and concentrated under reduced pressure. Purification by column chromatography (50-100% ethyl acetate in hexanes then 5% methanol in ethyl acetate) gave the product (1.85 g, 96%). 1HNMR (CDCl3) 400 MHz δ: 7.55 (d, J=8.7 Hz, 2H), 7.27 (d, J=8.7 Hz, 2H), 5.16 (d, J=6.9 Hz, 1H), 5.06 (d, J=6.9 Hz, 1H), 5.02 (d, J=6.9 Hz, 1H), 4.94 (d, J=6.9 Hz, 1H), 4.05 (br s, 1H), 1.22 (s, 9H). LCMS: 332, 334 [M+H].

1. stirringThe reaction mixture was stirred for an additional 30 min. at −78° C.
2. stirringAfter being stirred for 1 h at room temperature
3. customthe reaction mixture was quenched by addition of saturated ammonium chloride aqueous solution
4. extractionThe aqueous layer was extracted with ethyl acetate
5. washThe combined organic layer was washed with saturated sodium bicarbonate solution
6. dry with materialThe organics were dried over anhydrous sodium sulfate
7. concentrationconcentrated under reduced pressure
8. customPurification by column chromatography (50-100% ethyl acetate in hexanes