反应详情

A suspension of racemic-(trans)-2-(4-aminophenyl)cyclopropanecarboxylic acid (I-1) (0.28 g, 1.58 mmol) and 4-biphenylcarbaldehyde (0.32 g, 1.74 mmol) in dichloroethane (20 mL) were heated to reflux until a clear solution formed. The solution was cooled to RT then NaB(OAc)3H (0.50 g, 2.37 mmol) was added and stirred for 2 h. Water (50 mL) and dichloromethane (50 mL) were added and the organic layer was separated, dried over Na2SO4, filtered and concentrated. The crude material was purified on silica gel eluting with an increasing gradient from hexanes to 40% ethyl acetate/hexanes to give the title compound as a white solid (0.33 g, 61%). 1H NMR (400 MHz, DMSO) δ 12.15 (s, 1H), 7.65-7.59 (m, 4H), 7.46-7.41 (m, 4H), 7.34 (t, J=7.3 Hz, 1H), 6.84 (d, J=8.6 Hz, 2H), 6.51 (d, J=8.4 Hz, 2H), 6.22 (s, 1H), 4.29 (s, 2H), 2.23-2.18 (m, 1H), 1.62-1.57 (m, 1H), 1.32-1.28 (m, 1H), 1.21-1.16 (m, 1H). ES-MS m/z 344.2 (MH+).

1. temperaturewere heated
2. temperatureto reflux until a clear solution
3. customformed
4. customthe organic layer was separated
5. dry with materialdried over Na2SO4
6. filtrationfiltered
7. concentrationconcentrated
8. customThe crude material was purified on silica gel eluting with an increasing gradient from hexanes to 40% ethyl acetate/hexanes