Thermotropic Liquid-Crystalline Materials Based on Supramolecular Coordination Complexes

Abstract

Liquid crystals are among us, in living organisms and in electronic devices, and they have contributed to the development of our modern society. Traditionally developed by organic chemists, the field of liquid-crystalline materials is now involving chemists and physicists of all domains (computational, physical, inorganic, supramolecular, electro-chemistry, polymers, materials, etc.,). Such diversity in researchers confirms that the field remains highly active and that new applications can be foreseen in the future. In this review, liquid-crystalline materials developed around coordination complexes are presented, focusing on those showing thermotropic behavior, a relatively unexplored family of compounds.

The Contribution of Ruthenium in the Development of Metallomesogens

“…Arene ruthenium complexes are popular building blocks in supramolecular chemistry. [53] Addition of 1,4di(4-pyridinyl)benzene poly(arylester) derivative to the dinuclear arene-ruthenium complex [Ru 2 (p-cymene) 2 (donq)][DOS] 2 (donq = dihydroxynaphthoquinonato, DOS = dodecyl sulfate) has generated a tetranuclear metallacycle, which was isolated as its DOS salt (Figure 19). [54] The presence of four dendritic arms bearing cyano-biphenyl end-groups ensures mesomorphic properties above 50 °C.…”

Self-healing and shape memory functions exhibited by supramolecular liquid-crystalline networks formed by combination of hydrogen bonding interactions and coordination bonding

“…[1][2][3][4][5][6][7][8][9][10] In particular, combination of nano-science and supramolecular chemistry in liquid-crystalline (LC) assemblies is expected to provide new so materials with dynamic and anisotropic functions. [11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30] For example, development of supramolecular LC polymers has resulted in the induction of their stimuli-responsive and selfhealing properties as well as facile and simple formation processes. [26][27][28][29][30] Our strategy here is to develop hybrid supramolecular liquid crystals that exhibit polymer-like dynamic functions by the formation of rigid framework combining hydrogen bonds [31][32][33][34][35][36] and metal-ligand interactions 2,37-39 of low-molecular-weight compounds (Fig.…”