反应详情

温度

-78 °C

A dry-ice-acetone cooled 250 mL-RB flask is charged with anhydrous THF (30 ml) and diisopropylamine (2.2 g, 0.022 mol). A solution of butyl lithium in hexanes (1.6 M, 16 ml, 0.025 mol) is added over 30 minutes. After stirring at −78° C. for an additional 30 minutes, the mixture is warmed up to 0° C. and stirred for an hour. The mixture is cooled again in a dry-ice-acetone bath, and anhydrous ethyl acetate (1.76 g, 0.02 mol) is added dropwise over 30 minutes. After the mixture is stirred at −78° C. for 30 minutes, diisopropylsilanediyl bis(trifluoromethanesulfonate) (4.12 g, 0.01 mol) is added dropwise over 10 minutes. The reaction is quenched with water, and poured into ice-water. The organic layer is separated, and the aqueous layer is extracted with ether. The combined organic solution is washed with brine, dried over sodium sulfate, filtered, and the filtrate concentrated. The residue is purified by distillation in a Kugelrohr to yield 1.15 g (40%) of product as a yellowish oil. 1H NMR (500 MHz, CDCl3, in ppm) δ 4.09 (q, 4H, J=7.0 Hz), 1.99 (s, 4H), 1.24 (t, 6H, J=7.0 Hz), 1.12 (heptet, 2H, J=6.5 Hz), 1.06 (d, 12H, J=6.5 Hz).

1. temperaturethe mixture is warmed up to 0° C.
2. stirringstirred for an hour
3. temperatureThe mixture is cooled again in a dry-ice-acetone bath
4. stirringAfter the mixture is stirred at −78° C. for 30 minutes
5. customThe reaction is quenched with water
6. additionpoured into ice-water
7. customThe organic layer is separated
8. extractionthe aqueous layer is extracted with ether
9. washThe combined organic solution is washed with brine
10. dry with materialdried over sodium sulfate
11. filtrationfiltered
12. concentrationthe filtrate concentrated
13. distillationThe residue is purified by distillation in a Kugelrohr