Double-Circularly Connected Saloph-Belt Macrocycles Generated from a Bis-Armed Bifunctional Monomer

Abstract

Belt-shaped macrocycles possessing saloph units as their walls have been generated by the double-circular connection of a bis-armed bifunctional monomer bearing both o-phenylenediamine and salicylaldehyde functionalities. The saloph-belt macrocycles showed unique properties, such as the selective inclusion of fullerenes (K a(C70)/K a(C60) > 100), utilizing their rigid scaffolds.

The Green Box: An Electronically Versatile Perylene Diimide Macrocyclic Host for Fullerenes

“…In both solvents Green Box exhibits a preference for C 70 over C 60 which may result from a closer size and shape match with the larger ellipsoidal fullerene as well as enhanced electronic complementarity owing to C 70 being more electron deficient. ,,, In agreement with previously reported solution phase fullerene recognition studies, C 60 binding is stronger in toluene than in o -DCB due to the fact that the latter is a more competitive solvent. , However, on moving to the more polar solvent with C 70 , an enhanced stabilization of the stronger charge transfer aromatic stacking interactions appears to compensate for this effect. , …”

Self-Assembled Perylene Bisimide-Cored Trigonal Prism as an Electron-Deficient Host for C60 and C70 Driven by “Like Dissolves Like”

“…The key issue in the studies is the design and construction of supramolecular hosts. To date, a large number of macrocycles and several 3D cages have been developed as hosts. − Examination reveals that effective hosts generally possess two features: the first is size match of their cavities with the guests, fullerenes, and the second is electronic match of the hosts with the electron-poor guests, as evidenced by the fact that electron-rich moieties, such as porphyrins, pyrene, anthracenes, tetrathiafulvalenes, and carbon belts/bowls, were adopted as their main components. − However, electronic communication between the electron-rich host and the electron-deficient guest is sure to alter the primary properties of the guest as well as the host, which could induce similar problems encountered as in the chemical modifications. Therefore, it would be of great interest to develop electron-poor hosts that include the guests via other driving forces.…”

Site-Selective Ligand Bridging among Multiple Internal Coordination Sites of a Metallomacrocycle and Its Conformational Regulation

“…Metallomacrocycles and metallocages with internal coordination sites have a high potential to precisely control the positions of the guest ligands and overall shape of the assemblies by utilizing the directionality and reversibility of the coordination bonds. − When such coordinative hosts possess multiple coordination sites, it is difficult to control to which coordination sites the incoming guest ligands bind, because such systems often result in a random, uncontrolled mixture. Many metal–organic hosts utilizing coordination bonds have two coordination sites that bind one ditopic ligand. − Metallohosts possessing more than two coordination sites are often utilized to capture the guests possessing the same number of coordination valences as the hosts. ,, As an example of site-selective linking, a rod-shaped ditopic sulfonate ligand was used to connect diagonal two metal vertices of an octahedral capsule .…”