Protonated Amino Acid-Induced One-Handed Helicity of Polynorbornene Having Monoaza-18-crown-6 Pendants
作者:Renjie Ji、Chih-Gang Chao、Yen-Chin Huang、Yi-kang Lan、Cheng-Lu Lu、Tien-Yau Luh
DOI:10.1021/ma1014726
日期:2010.11.9
ether pendant resulting in unidirectional orientation of the pendants leading to a helical scaffold. The corresponding dimer 10 with the same isotactic stereochemistry as that of polynorbornene 7a behaves similarly to exhibit bisignate CD curve upon treatment with protonated alanine. On the other hand, polynorbornene with monoaza-15-crown-5 (7b) does not exhibit any CD response under the same conditions
与质子化的氨基酸络合后,获得附有monoaza-18-crown-6(7a)的单手螺旋聚降冰片烯。观察到的合作性是由军士士兵效应和多数规则所揭示的。当使用位阻氨基酸(如苯丙氨酸,异缬氨酸或脯氨酸),氨基酸的酯和氨基醇时,CD光谱中的Δε值会大大降低。质子化的铵离子可与冠醚部分形成配合物,而羧酸可与相邻的冠醚侧基形成氢键,导致侧基的单向取向,从而导致螺旋支架。相应的二聚体10具有与聚降冰片烯7a相同的全同立构立体化学质子化的丙氨酸处理后的行为类似,表现出双信号CD曲线。另一方面,在相同条件下,聚降冰片烯与monoaza-15-crown-5(7b)不会表现出任何CD反应。