反应详情

To a solution of 4-[2-ethoxy-2-(2,2,2-trichloro-ethoxycarbonyl)-ethyl]-benzoic acid 4-methane sulfonyloxy-benzyl ester (0.02 g, 0.036 mmol) in dry DCM (2 mL) was first added zinc dust (0.047 g, 0.722 mmol), then acetic acid (1.08 mL, 18.06 mmol) at 0° C. The resulting inhomogeneous mixture was stirred for 17 h without removing the ice bath. The zinc was filtered off and washed with DCM and MeOH and the remaining filtrates were combined and evaporated under reduced pressure. The crude product was purified by column chromatography using DCM/MeOH (92:8) as the eluent. The title compound was obtained as an oil (0.005 g, 36%). 1H NMR (400 MHz, CDCl3): δ 7.91-7.93 (d, 2H), 7.42-7.44 (d, 2H, 7.19-7.24 (m, 4H), 5.27 (s, 2H), 4.03 (m, 1H), 3.52 (m, 1H), 3.37 (m, 1H), 2.99-3.14 (m, 2H), 3.08 (s, 3H), 2.63 (t, 3H). Mass Spectrum: M−H+ 421.23.

1. customat 0° C
2. customwithout removing the ice bath
3. filtrationThe zinc was filtered off
4. washwashed with DCM and MeOH
5. customevaporated under reduced pressure
6. customThe crude product was purified by column chromatography