反应详情

温度

134 °C

A mixture of butyric acid (1.0 g, 11.35 mmol), bromoacetaldehyde dimethyl acetal (2.25 mL, 19.13 mmol), tetrabutylammonium bromide (1.83 g, 5.67 mmol) and K2CO3 (1.56 g, 11.35 mmol) in 10 mL of anhydrous CH3CN was stirred at 134° C. for 16 h in a sealed tube. It was cooled to room temperature, water was added and the mixture was extracted with Et2O (3×120 mL). The combined organic phases were washed with saturated NaCl (2×60 mL), dried over Na2SO4, filtered and concentrated in vacuo. The residue was purified by flash chromatography on silica gel using 20-30% ethyl acetate/hexanes to give the product 43a (1.56 g, 78%). 1H NMR (400 MHz, CDCl3) δ 0.90 (t, J=7.43 Hz, 3H), 1.60 (sextet, J=7.43, 7.04 Hz, 2H), 2.24 (t, J=7.04 Hz, 2H), 3.36 (s, 6H), 4.08 (d, J=5.3 Hz, 2H), 4.54 (t, J=5.3 Hz, 1H).

1. temperatureIt was cooled to room temperature
2. extractionthe mixture was extracted with Et2O (3×120 mL)
3. washThe combined organic phases were washed with saturated NaCl (2×60 mL)
4. dry with materialdried over Na2SO4
5. filtrationfiltered
6. concentrationconcentrated in vacuo
7. customThe residue was purified by flash chromatography on silica gel using 20-30% ethyl acetate/hexanes