反应详情

温度

-78 °C

N,N-diethyl 4-iodo-benzamide (3.1 g, 10 mmol) was dissolved in dry toluene/THF (9:1, 200 mL) and cooled to −78° C. under nitrogen. n-BuLi (7.8 mL, 1.3 M in hexane, 10 mmol) was added dropwise during 5 to 10 min. After further 5 min, 3 (1.0 g, 3.4 mmol) was added dissolved in toluene (1 mL). The solution was stirred 10 min, then NH4Cl (aq.) was added. Concentration, aqueous workup and chromatography on silica gave a total of 0.70 g (44%) of a 70:30 mixture of diastereomers. The pure major isomer 5 (0.37 g) was obtained by one more chromatography. 1H NMR (CDCl3): δ1.2 (m, 6H), 2.4 (s, 3H), 3.4 (m, 4H), 6.35 (d, J=7.5 Hz, 1 H), 6.61 (d, J=7.5 Hz,1 H), 7.15-7.55 (m, 11H), 7.75 (m, 1H), 8.12 (m, 1H), 8.75 (m, 1H).

1. concentrationConcentration, aqueous workup and chromatography on silica
2. customgave
3. additiona total of 0.70 g (44%) of a 70:30 mixture of diastereomers