通过复杂的构建块扩大自我组装的树枝和超分子树枝体的结构多样性
Virgil Percec1, Betty C Won, Mihai Peterca
1Roy & Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323, USA. percec@sas.upenn.edu
Journal of the American Chemical Society
|August 21, 2007
概括
研究人员设计了新的AB4和AB5树突构建块,从而产生了具有独特架构的复杂超分子树突. 这些树枝状树体表现出不寻常的螺旋结构,并自组装成松树般的柱子和球形构造.
科学领域:
- 超分子化学 超分子化学
- 丹德里默的合成方式
- 材料科学是一种材料科学.
背景情况:
- 乙烯树枝被广泛研究,但它们的构造局限性是众所周知的.
- 复杂的树突结构很难设计和合成.
- 树突的自我组装决定了它们的宏观性质.
研究的目的:
- 为了设计和合成新的AB4和AB5树突构建块.
- 为了研究混合树枝状体的自我组装和构造行为.
- 为了发现新的超分子结构和螺旋顺序.
主要方法:
- 合成AB4和AB5树突构建块的合成.
- 自组合混合树枝状体的结构和逆结构分析.
- 使用螺旋式衍射理论对面纤维的X射线衍射分析.
主要成果:
- 通过分子内背折叠发现了不寻常的形和形树枝.
- 形成类似松树的柱子,7/2螺旋顺序从背折叠的圆状树.
- 自组装成球形树枝状 (密度和不太密度的中心) 和金字塔形柱子,从冠状树枝状的5/1螺旋顺序.
结论:
- 新的AB4和AB5构建块使复杂的树突结构成为可能.
- 内部分子的背向折叠导致独特的形和形树突形状.
- 螺旋衍射理论成功地描述了超分子树状体中的新型远程螺旋结构.
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