协价稳定:来自可逆金属离子导向自组合的坚固分子正方形
Alexandre G L Olive1, Kamil Parkan, Cecile Givelet
1Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309-0215, USA.
Journal of the American Chemical Society
|November 5, 2011
概括
研究人员将脆弱的自我组装分子转化为坚固的结构. 这种方法使用模板导向合成来将dative键转换为共价键,将装配方便与结构耐用性相结合.
科学领域:
- 超分子化学 超分子化学
- 材料科学是一种材料科学.
- 有机合成 有机合成
背景情况:
- 超分子自我组装为复杂的分子架构提供了方便的途径.
- 然而,这些结构往往依赖于弱相互作用,导致有限的稳定性.
- 开发方法来提高自组装材料的强度至关重要.
研究的目的:
- 开发一种方法,将不稳定的超分子组合转化为强大的共价结构.
- 用可逆自组装过程作为强大的合成模板.
- 在最终的坚固结构中实现相同的拓和相似的几何结构.
主要方法:
- 采用过渡金属导向的棒和连接器分子的可逆自组装.
- 使用铜 (I) 催化反应,以以乙烯基末端的类似物取代氨酸末端的组件.
- 将原始-键转换为强大的共价碳-键.
主要成果:
- 成功地将一个脆弱的超分子结构模板成一个坚固的模拟.
- 实现了高产量,并保留了原始组件的拓和几何.
- 展示了一种新的策略,结合了可逆自组合和共价合成的优势.
结论:
- 开发的方法为复杂的分子架构提供了强大的途径.
- 这种方法将超分子化学的效率与共价材料的稳定性结合在一起.
- 为创建持久,复杂的分子结构提供了一种多功能策略.
相关概念视频
Complexation Equilibria: Factors Influencing Stability of Complexes
In complexation reactions, metal cations are the electron pair acceptors, and the ligands are the electron pair donors. The stability of the metal complexes depends primarily on the complexing ability of the central metal ion and the nature of the ligands. Generally, the complexing ability of the metal ion depends on the size and charge of the ion. As the metal ion size increases, the stability of the metal complexes decreases, provided that the valency of the metal ion and the ligands remain...
Valence Bond Theory
Coordination compounds and complexes exhibit different colors, geometries, and magnetic behavior, depending on the metal atom/ion and ligands from which they are composed. In an attempt to explain the bonding and structure of coordination complexes, Linus Pauling proposed the valence bond theory, or VBT, using the concepts of hybridization and the overlapping of the atomic orbitals. According to VBT, the central metal atom or ion (Lewis acid) hybridizes to provide empty orbitals of suitable...
Valence Bond Theory
Overview of Valence Bond Theory
Complexation Equilibria: Overview
Complexation reactions take place when dative or coordinate covalent bonds form between metal ions and ligands. The compounds formed in these reactions are called coordination compounds. The number of bonds formed between the metal ion and the ligands is called its coordination number. Generally, most metal ions in an aqueous solution are solvated by water molecules and thus exist as aqua complexes.
The equilibrium constant of the complexation reaction is represented as the formation constant...
The equilibrium constant of the complexation reaction is represented as the formation constant...
Metal-Ligand Bonds
The hemoglobin in the blood, the chlorophyll in green plants, vitamin B-12, and the catalyst used in the manufacture of polyethylene all contain coordination compounds. Ions of the metals, especially the transition metals, are likely to form complexes.
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
Ionic Bonding and Electron Transfer
Ions are atoms or molecules bearing an electrical charge. A cation (a positive ion) forms when a neutral atom loses one or more electrons from its valence shell, and an anion (a negative ion) forms when a neutral atom gains one or more electrons in its valence shell. Compounds composed of ions are called ionic compounds (or salts), and their constituent ions are held together by ionic bonds: electrostatic forces of attraction between oppositely charged cations and anions.


