反应详情

To a solution of ethyl 2-cyano-3-methylbut-2-enoate (0.91 mL, 6 mmol) in ether (4 mL) under N2 was added 1.0 M benzylmagnesium chloride in ether (9 mL, 9 mmol) dropwise to give a pale yellow solution. The reaction was stirred at room temperature for 3 h, and was then cooled to 0° C. and acidified with 10% HCl (10 mL). The organic layer was isolated, washed with water and brine, dried over Na2SO4, and concentrated under reduced pressure to give bright yellow oil. Purification by flash column chromatography (10% ethyl acetate in hexanes, Rf=0.26) gave the title compound as a pale yellow oil (1.08 g, 73.5%). 1H NMR (500 MHz, CDCl3) δ 8.02 (d, J=7.6 Hz, 1H), 7.51 (t, J=7.6 Hz, 1H), 7.32 (t, J=7.6 Hz, 1H), 7.22 (d, J=7.6 Hz, 2H), 4.22 (m, 2H), 3.44 (s, 1H), 3.07 (d, J=16.5 Hz, 1H), 2.83 (d, J=16.5 Hz, 1H), 1.28 (t, J=7.1 Hz, 2H), 1.18 (s, 3H), 1.15 (s, 3H).

1. customto give a pale yellow solution
2. temperaturewas then cooled to 0° C.
3. customThe organic layer was isolated
4. washwashed with water and brine
5. dry with materialdried over Na2SO4
6. concentrationconcentrated under reduced pressure
7. customto give bright yellow oil
8. customPurification by flash column chromatography (10% ethyl acetate in hexanes, Rf=0.26)