Tricks of light on helices: transformation of helical polymers by photoirradiation.
Tricks of light on helices: transformation of helical polymers by photoirradiation.
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DOI：
10.1002/tcr.201300042
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发表时间：
2014-06
期刊：
影响因子：
6.6
通讯作者：
T. Nakano
中科院分区：
文献类型：
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作者：
T. Nakano
利用光实现了以下聚合物结构转变：聚(9,9-二正辛基芴-2,7-二基)的优先螺旋形成、聚(2,7-双(4-叔丁基苯基)芴-9-丙烯酸酯)和聚(2,5-双[4-((S)-2-甲基丁氧基)苯基]苯乙烯)的螺旋外消旋化(螺旋-螺旋转变)以及聚(2,5-双[4-((S)-2-甲基丁氧基)苯基]苯乙烯)的螺旋分解聚(2,7-双(4-叔丁基苯基)-9-甲基芴-9-基丙烯酸酯)和聚(2,7-双(4-叔丁基苯基)芴-9-基甲基丙烯酸甲酯)。尽管这些类型的转变和化学转变主要是使用热或化学物质作为刺激来研究的，但光也可以引起这些结构改变。在螺旋结构和螺旋-螺旋转变中，关键转变是聚合物侧链或主链中联苯或芳基-芳基单元的扭转共面构象变化。此外，螺旋-螺旋转变仅由光引起，而不是由热引起。本综述中讨论的例子有望引发手性聚合物合成和反应的新方向。
The following polymer structural transitions were achieved using light: preferred-handed helix formation for poly(9,9-di-n-octylfluoren-2,7-diyl), helix racemization (helix-helix transition) for poly(2,7-bis(4-t-butylphenyl)fluoren-9-yl acrylate) and poly(2,5-bis[4-((S)-2-methylbutyloxy)phenyl]styrene), and helix decomposition for poly(2,7-bis(4-t-butylphenyl)-9-methylfluoren-9-yl acrylate) and poly(2,7-bis(4-t-butylphenyl)fluoren-9-ylmethyl methacrylate). Although these types of transitions and chemical transformations have been studied mainly using heat or chemicals as stimuli, light can also cause these structural alterations. In the helix construction and the helix-helix transition, a key transition is a twist-coplanar conformational change of a biphenyl or an aryl-aryl unit in the side chain or the main chain of the polymer. Furthermore, the helix-helix transition was caused only by light and not by heat. The examples discussed in this review are expected to trigger off a new direction in synthesis and reaction of chiral polymers.