Electronic effects on the amide E-/Z-preference of N-benzoyl-carbazole derivatives
作者:Susumu Kayama、Norihiko Tani、Hidetsugu Tabata、Tetsuta Oshitari、Hideaki Natsugari、Hideyo Takahashi
DOI:10.1016/j.tetlet.2016.04.059
日期:2016.6
N-2′,4′,6′-Trisubstituted 3-/4-substituted carbazole derivatives exist as mixtures of E-/Z-amide conformers. It was found that the ratio of the two conformers is controlled by the electronic properties of the 3-/4-substituents. The 3-ammonium-6-t-butyl-carbazole derivative 3s, in which the electronic character of each benzene ring of carbazole was properly tuned, provided the best preference for the
N -2',4',6'-三取代的3- / 4-取代的咔唑衍生物以E- / Z-酰胺构象异构体的混合物存在。发现两种构象异构体的比例受3- / 4-取代基的电子性质控制。咔唑的每个苯环的电子特性均经过适当调节的3-铵-6-叔丁基咔唑衍生物3s为Z-构象异构体提供了最佳选择(E:Z = 1:2.50)。