Study on the integration of coordination compounds and chemistry of molecular self-assembly

From the viewpoint of molecular self-assembly, we have tackled unresolved issues in coordination chemistry. In this review, an overview of these studies will be presented. 1 Development of one-dimensional metal complexes whose electronic or spin structures are regulated based on self-assembly: By introducing synthetic lipids as counter anions of one-dimensional halogenbridged mixed-valence complexes, we have developed a methodology for dispersing one-dimensional complex chains as nanowires in organic solvents. Thermochromism was observed in organic solvents, indicating that one-dimensional electronic structures form in response to self-assembly. We also observed solvatochromism in the lipophilic metal complexes. In the linear Fe(II) triazole complexes, the low-spin state is specifically stabilized when dispersed in low-polarity solvents, and spin conversion was observed for the solution-dispersed nanowires. Furthermore, the first example of heat-set gel formation was found for Co(II) triazole complex in organic media. We found that the change in coordination structure leads to unique complex solution properties. 2 Discovery of dissipative nanostructures. 3 Adaptive self-assembly in aqueous coordination nanoparticles. 4 Development of photon upconversion molecular systems based on self-assembly. These studies have opened up a new research area between molecular organization chemistry and coordination chemistry, which would provide a basis for molecular systems chemistry.