A Facile Synthesis of Unusual Liquid-Crystalline Gold(I) Dicarbene Compounds

摘要

Self-assembly of molecules through weak forces such as hydrogen bonds and hydrophobic and electrostatic interactions to form supramolecular aggregates has become a major research area in recent years. While conventional liquid crystals (LC) are one aspect of this subject, metal-containing liquid crystals (metallomesogens, MLCs) provide new possibilities for varying the structure and properties such as color and polarizability. Designing stable MLCs remains a challenge. Many MLCs decompose at the clearing point; their applications are therefore limited. We are interested in the chemistry of gold(I). Gold(I) compounds are used in medicine, they exhibit remarkable pho-tophysical properties, and aurophilic interactions are important in the constructionof supramolecules. The above reasons and the inherent thermal stability of metal complexes of 1,3-disubstituted imidazol-2-ylidene (imy) led us to investigate the synthesis of liquid-crystalline bis(1,3-dialkylbenzimidazol-2-ylidene)gold(I) bromide [{(C_nH_(2n + 1)_2-bimy}_2Au]Br (n = 12, 14, 16).