在光学无活性的聚4-碳氧异化物 (poly-4-carboxyphenyl isocyanide) 上用奇拉胺诱导宏分子性:聚异化物 (poly-异化物) 衍生物的动态形态转换
Masayoshi Ishikawa1, Katsuhiro Maeda, Eiji Yashima
1Department of Molecular Design and Engineering, Graduate School of Engineering, Nagoya University, Chikusa-ku, Nagoya 464-8603, Japan.
Journal of the American Chemical Society
|June 20, 2002
概括
在光学上不活跃的多异酸衍生物通过性刺激获得光学活性. 这种通过诱导的循环二元化观察到的动态形状变化,表明了新的功能材料潜力.
科学领域:
- 聚合物化学 聚合物化学
- 材料科学 材料科学 材料科学
- 超分子化学 超分子化学
背景情况:
- 目前正在探索光学活性聚酸的功能性材料.
- 具有庞大的侧组的多化通常采用稳定的螺旋形状.
- 聚异化 (PPI) 衍生物的形状特征仍在争论中.
研究的目的:
- 调查聚4-碳酸异化物 (poly-1) 的构造性行为,这是一种光学不活性的PPI衍生物.
- 确定外部性刺激是否可以在聚合物骨干中诱导光学活动.
- 探索PPI衍生品中螺旋性诱导的机制.
主要方法:
- 聚4-碳氧异化物 (poly-1) 的合成
- 光谱分析包括紫外线可见光谱和诱导圆形二重化 (ICD).
- (1)H NMR光谱和分子动态模拟用于分析形状变化.
主要成果:
- 在DMSO中与奇拉氨基胺相互作用时,光学不活性的聚-1呈现诱导的循环二元化 (ICD).
- 随着时间的推移,ICD强度增加,达到最初值的三倍.
- 在poly-1及其衍生物中观察到缓慢的构造变化,这表明了动态的近皮构造.
结论:
- 具有较小体积的替代剂的PPI可能具有亲手的s-trans (zigzag) 形状,而不是4(1) 螺旋.
- 能够与性化合物相互作用的功能组可以诱导一个动态的,单手螺旋形状.
- 这项研究揭示了通过动态形状转换在聚酸中诱导螺旋性的一种机制.
相关概念视频
Stereoisomerism
Isomerism in Complexes
Isomers are different chemical species that have the same chemical formula.
Transition metal complexes often exist as geometric isomers, in which the same atoms are connected through the same types of bonds but with differences in their orientation in space. Coordination complexes with two different ligands in the cis and trans positions from a ligand of interest form isomers. For example, the octahedral [Co(NH3)4Cl2]+ ion has two isomers (Figure 1) In the cis...
Isomers are different chemical species that have the same chemical formula.
Transition metal complexes often exist as geometric isomers, in which the same atoms are connected through the same types of bonds but with differences in their orientation in space. Coordination complexes with two different ligands in the cis and trans positions from a ligand of interest form isomers. For example, the octahedral [Co(NH3)4Cl2]+ ion has two isomers (Figure 1) In the cis...
Photochemical Electrocyclic Reactions: Stereochemistry
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Selection Rules: Photochemical Activation
Selection Rules: Photochemical Activation
Radical Formation: Homolysis
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Polymer Classification: Stereospecificity
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Cycloaddition Reactions: MO Requirements for Photochemical Activation
Some cycloaddition reactions are activated by heat, while others are initiated by light. For example, a [2 + 2] cycloaddition between two ethylene molecules occurs only in the presence of light. It is photochemically allowed but thermally forbidden.
[3,3] Sigmatropic Rearrangement of Allyl Vinyl Ethers: Claisen Rearrangement
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