A Directly-linked Cyclic Pyrene Tetramer as a Back-to-back Receptor for Two Fullerenes

As a homoditopic back-to-back host molecule, a cyclic 1,8-pyrenylene tetramer CP4 having two cavities for guest complexation was investigated. The unique two-face structural feature of CP4 allows it to bind spherical pristine fullerenes. The host-guest interactions were characterized by 1H NMR spectroscopy and single-crystal X-ray diffraction analysis.journal articl

Direct borylation of terrylene and quaterrylene

The preparation of large rylenes often needs the use of solubilizing groups along the rylene backbone, and all the substituents of the terrylenes and quaterrylenes were introduced before creating the rylene skeleton. In this work, we successfully synthesized 2,5,10,13-tetrakis(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)terrylene (TB4) by using an iridium-catalyzed direct borylation of C?H bonds in terrylene in 56% yield. The product is soluble in common organic solvents and could be purified without column chromatography. Single crystal X-ray diffraction analysis revealed that the terrylene core is not disturbed by the substituents and is perfectly flat. The photophysical properties of TB4 are also unchanged by the substituents because the carbon atoms at 2,5,10,13-positions have less coefficients on its HOMO and LUMO, estimated by theoretical calculations. Finally, the same borylation reaction was applied for quaterrylene, resulting in the formation of soluble tetra-borylated quaterrylene despite a low yield. The post modification of rylenes enables us to prepare their borylated products as versatile units after creating the rylene skeletons.journal articl