反应详情

温度

0 °C

To a solution of diethyl zinc (20.30 ml, 1M solution in hexane, 20.30 mmol) in DCM (25 ml) at 0° C. was added a solution of trifluoroacetic acid (1.56 ml, 20.30 mmol) in DCM (10 ml) dropwise. The mixture was stirred at 0° C. for 20 min and then a solution of CH2I2 (1.64 ml, 20.30 mmol) in DCM (10 ml) was added. After stirring for an additional 20 min a solution of 1-bromo-4-isopropenylbenzene (346 mg, 1.76 mmol) in DCM (10 ml) was added. The reaction mixture was slowly warmed to rt and stirring was continued for 16 h. Pentane was added and the mixture was washed with 1M HCl, sat. NaHCO3, sat. Na2SO3 and brine. The organic layer was dried (MgSO4), filtered, concentrated in vacuo to give a residue which was purified by flash column chromatography (100% pentane). The product (2.12 g, 86%) was isolated as a 4:1 mixture of product to methyleneiodide as a colorless oil. 1H NMR (CDCl3, 300 MHz): δ 7.38 (d, J=8.5 Hz, 2H), 7.12 (d, J=8.5 Hz, 2H), 1.37 (s, 3H), 0.84-0.79 (m, 2H), 0.76-0.71 (m, 2H).

1. additionwas added
2. temperatureThe reaction mixture was slowly warmed to rt
3. stirringstirring
4. waitwas continued for 16 h
5. washthe mixture was washed with 1M HCl, sat. NaHCO3, sat. Na2SO3 and brine
6. dry with materialThe organic layer was dried (MgSO4)
7. filtrationfiltered
8. concentrationconcentrated in vacuo
9. customto give a residue which
10. customwas purified by flash column chromatography (100% pentane)