Analytical Application of Molecular Recognition by Photochemistry of Excited States

合成了分子中含有两个蒽基与聚醚结合的新化合物。这些化合物能识别处于蒽基团激发态的分子或离子。当这些试剂被紫外光激发时，在蒽环上发生光二聚化，形成三个区域异构体。碱土金属离子（如钙离子）的加入改变了区域异构体的比例。为了解释这一现象，对碱土金属离子的络合物形成常数进行了计算。然而，光度法如荧光或吸收光谱法引起光二聚化。采用H-NMR滴定法测定其形成常数。从形成常数的结果来看，我们发现钙离子在碱土金属离子中形成最稳定的络合物。配位时的化学位移变化表明，钙配合物采用最适合光二聚化的构象。合成了一种新的化合物，该化合物具有两个蒽基单元，通过芳香羧胺部分与聚醚相连。含2-蒽类似物的化合物与钙离子具有较强的络合能力，在络合时荧光发射明显增加（40倍）。还合成了含有萘乙酰胺单元的新化合物。虽然在萘和酰胺基团之间插入了亚甲基，但萘的激发态被淬灭，几乎没有发射。这可能是TICT机制和PET（光致电子转移）机制共同作用的结果。该化合物与钙离子的配合作用引起了萘部分的发射，这种发射是由于配合物的形成降低了TICT的猝灭效率。

New compounds which contain two anthracene units in the molecules combining with polyether were synthesized. These compounds will recognize molecules or ions at the excited state of the anthracene moieties.When these reagents are excited by UV light, the photo dimerization at anthracen rings occurred, and three regio-isomers formed. The ratio of the regio-isomers was changed by the addition of alkaline earth metal ions such as calcium ion. To elucidate this phenomenon, the complex formation constants for alkaline earth metal ions were evaluated. However, photometric method such as fluorescence or absorption spectrometry caused the photo dimerization. H-NMR titration method was adopted to evaluate the formation constants. From the result of formation constants, we found that calcium ion forms the most stable complex in alkaline earth metal ions. The chemical shift change at the complexation shows that the calcium complex takes the most suitable conformation for photo dimerization.A new compound which has two anthracene units linked to polyether via aromatic carboxamide moiety was synthesized. The compound with 2-anthracene analogue has large complexing ability with calcium ion, and shows large increase of fluorescence emission (40 fold) at the complexation.Tne new compounds which have naphthalene acetamide units was also synthesized. Although the methylene units was inserted between naphthalene and amide moietys, the excited state of naphthalene has been quenched and little emission was observed. This fact may be caused by combination of TICT mechanism and PET (photo induced electron transfer) mechanism. The conplexation of this compound with calcium ion induced an emission from naphthalene moiety, and this emission was caused from a decrease of TICT quenching efficiency by the complex formation.