Supramolecular Chirogenesis Engineered by Pt(II)···Pt(II) Metal–Metal Interactions

Abstract

Supramolecular chirogenesis represents an effective way to induce chirality at the supramolecular level. For the previous host–guest chirogenic systems, metal–ligand coordination, hydrogen bonding, π–π stacking and hydrophobic interactions have been mainly employed as the non-covalent driving forces. In this study, Pt(II)···Pt(II) metal–metal interactions have been engineered to induce supramolecular chirogenesis, by forming non-covalent clipping structures between chiral platinum receptors and achiral platinum guests together. This results in the emergence of Cotton effects in the metal–metal-to-ligand charge transfer region, ascribed to chirality transfer from trans-1,2-diamide cyclohexane unit on chiral receptors to Pt(II)---Pt(II) non-covalent interacting sites. Supramolecular chirogenesis can be further transferred from organic to aqueous solutions, with higher resistance to concentration and temperature variations in the latter medium. Overall, the current study provides new avenues toward supramolecular chirality systems with tailored properties.