Switching of Molecular Insertion in a Cyclic Molecule via Photo- and Thermal Isomerization
Switching of Molecular Insertion in a Cyclic Molecule via Photo- and Thermal Isomerization
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通过光异构化和热异构化切换环状分子中的分子插入
DOI：
10.1021/ic200145h
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发表时间：
2011
期刊：
影响因子：
4.6
通讯作者：
Hiroshi Nishihara
中科院分区：
文献类型：
--
作者：
Satoshi Umeki;Shoko Kume;Hiroshi Nishihara
合成了两个新的环状配体：两个反式偶氮苯和一个联吡啶的配体trans 2-oAB-O 13和两个反式偶氮苯和两个联吡啶的配体trans 2-oAB-bpy。这两个配体进行可逆的反-顺异构化的偶氮苯部分。通过1H NMR光谱法对1 h光照制备的光稳定态进行评估，反式2型：反式-顺式：顺式2型的摩尔比对于oAB-O 13为0.13：0.27：0.60（365 nm照射）和0.41：0.47：0.12（436 nm照射），而对于oAB-bpy为0.18：0.12：0.70（365 nm照射）和0.36：0.43：0.21（436 nm照射）。当trans 2-oAB-O 13与Cu（I）混合时，联吡啶单元和聚醚链都与铜中心配位。加入非环状联吡啶配体trans 2-oAB-2 OH，得到双（联吡啶）铜（I）配合物[Cu（trans 2-oAB-O 13）（trans 2-oAB-2 OH）] BF 4。双（联吡啶）配体trans 2-oAB-bpy与Cu（I）形成1：1配合物[Cu（trans 2-oAB-bpy）] BF 4。[Cu（cis 2-oAB-bpy）] BF 4不与含有两个偶氮苯和一个联吡啶的非环状配体oAB发生配体取代反应，而在ofoAB存在下，其热异构化导致[Cu（trans 2-oAB-bpy）（trans 2-oAB）] BF 4的形成，表明异构化和配体交换反应通过环状配体的构象变化同步进行。
Two new cyclic ligands were synthesized: a ligand with twotrans-azobenzene moieties and one bipyridine moiety,trans2-oAB-O13, and a ligand with twotrans-azobenzene moieties and two bipyridine moieties,trans2-oAB-bpy. Both ligands underwent reversible trans-cis isomerization at the azobenzene moieties. The mole ratios of thetrans2form:trans-cisform:cis2form, evaluated by1H NMR spectroscopy of the photostationary states prepared by 1 h illumination, were 0.13:0.27:0.60 (365 nm irradiation) and 0.41:0.47:0.12 (436 nm irradiation) foroAB-O13, and 0.18:0.12:0.70 (365 nm irradiation) and 0.36:0.43:0.21 (436 nm irradiation) foroAB-bpy. Whentrans2-oAB-O13 was mixed with Cu(I), both the bipyridine units and the polyether chains coordinated to the copper center. Addition of a noncyclic bipyridine ligand,trans2-oAB-2OH, afforded a bis(bipyridine)copper(I) complex, [Cu(trans2-oAB-O13)(trans2-oAB-2OH)]BF4. The bis(bipyridine) ligand,trans2-oAB-bpy, formed a 1:1 complex with Cu(I), [Cu(trans2-oAB-bpy)]BF4. [Cu(cis2-oAB-bpy)]BF4did not undergo the ligand substitution reaction with a noncyclic ligand with two azobenzene moieties and one bipyridine moiety,oAB, whereas its thermal isomerization in the presence ofoAB caused the formation of [Cu(trans2-oAB-bpy)(trans2-oAB)]BF4, indicating that the isomerization and ligand exchange reactions synchronized via a conformational change of the cyclic ligand.