Role of free space and weak interactions on geometric isomerization of stilbenes held in a molecular container
Role of free space and weak interactions on geometric isomerization of stilbenes held in a molecular container
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自由空间和弱相互作用对分子容器中二苯乙烯几何异构化的作用
DOI：
10.1039/c1pp05035d
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发表时间：
2011
影响因子：
3.1
通讯作者：
V. Ramamurthy
中科院分区：
文献类型：
--
作者：
A. Parthasarathy;V. Ramamurthy
众所周知，烯烃的光化学几何异构化依赖于它发生的介质。在灵活的生物系统和不灵活的晶体中都有最高的选择性。我们在本报告中提出的结果表明，即使在各向同性的柔性水介质中，只要它发生在一个孤立的水溶性不灵活的反应腔内，异构化也是选择性的。通过检查包含在有机空腔和八乙酸中的12种二苯乙烯（反式和相应的顺式异构体）的光化学，我们已经能够探索“自由体积”，“弱相互作用”和“超分子空间效应”在几何异构化过程中的作用。当介质通过弱相互作用、超分子空间效应和受控制的自由空间（自由体积）限制烯烃的迁移率时，几何异构化具有选择性。
Photochemical geometric isomerization of olefins is long known to depend on the medium in which it occurs. Highest selectivity occurs in flexible biological systems as well as in inflexible crystals. We present results in this report that suggest the isomerization is selective even in an isotropic flexible aqueous medium provided it occurs within an isolated water-soluble inflexible reaction cavity. By examining the photochemistry of twelve stilbenes ( trans and corresponding cis isomers) included in an organic cavitand octa acid we have been able to probe the role of ‘free volume’, ‘weak interactions’ and ‘supramolecular steric effects’ on the geometric isomerization process. Geometric isomerization becomes selective when the olefin’s mobility is restricted by the medium through weak interactions, supramolecular steric effects and controlled free space (free volume).