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A series of iridium‐polymer complexes containing bipyridonate moieties were synthesized. The high catalytic performance of the iridium‐polymer complex for the dehydrogenative oxidation of alcohols was demonstrated. Notably, the bipyridonate moiety in the polymer structure acts as a chemically non‐innocent "functional ligand", realizing the enhancement of dehydrogenation process. While numerous metal‐polymer catalysts have been reported so far, to our knowledge, introducing a "functional ligand" into a polymer chain that can operate cooperatively with transition metals by changing their structures during the catalytic processes is rare. The iridium‐polymer complex could be easily separated from the product and recovered by precipitation upon the addition of methanol after the catalytic reaction. Furthermore, the recovered catalyst could be reused without loss of catalytic efficiency at least ten times. [ABSTRACT FROM AUTHOR]

Optically active oligo(o-phenylene)-layered molecules were synthesized from planar chiral enantiopure [2.2]paracyclophane. Their structures and optical properties were characterized by experimental and theoretical approaches. The axial chiralities between phenylene rings of the oligo(o-phenylene)s were controlled by the planar chirality to form one-handed helical structures. The o-quinquephenyl-layered molecule was emissive, and circularly polarized luminescence was observed with a high anisotropy factor (‖glum‖ value) of 0.012. [ABSTRACT FROM AUTHOR]

Since the development of the first method for porphyrin synthesis by Rothemund in 1935, porphyrin derivatives have been widely investigated and have played an essential role in chemical sciences. Most synthetic routes of porphyrins involve oxidative aromatization. Herein, we present a synthetic method to produce ABCD‐porphyrins, including chiral ones, through a one‐pot reaction involving "coordination, cyclization, and dehydrative aromatization" using a mono‐dipyrrinatoPt(II)Cl(COE) (COE=cyclooctene) complex as a platinum template. [ABSTRACT FROM AUTHOR]

The correlation between the orientation of the two π‐electron systems and the chiroptical properties was investigated using two types of optically active X‐shaped molecules consisting of planar chiral [2.2]paracyclophanes. The X‐shaped molecules exhibited high photoluminescence quantum efficiencies and good circularly polarized luminescence properties with relatively high anisotropy factors of the order of 10−3. It was experimentally and theoretically elucidated that the chiroptical properties of the two molecules were almost identical, regardless of the orientation of the stacked π‐electron systems. [ABSTRACT FROM AUTHOR]

Abstract: A [2.2]paracyclophane-based through-space-conjugated tetramer comprising four partially stacked π-electron systems was designed and synthesized, with a large overlap integral between the photoluminescence spectrum of the terminal π-electron system of [...]

This study reports the synthesis of optically active cyclic tetramers comprising four stacked π‐electron systems from two enantiomerically pure [2.2]paracyclophane compounds (bis‐(para)‐pseudo‐ortho‐ and bis‐(para)‐pseudo‐meta‐tetrasubstituted [2.2]paracyclophane compounds). Depending on the combination of the absolute configurations of the planar chiral pseudo‐ortho‐ and pseudo‐meta‐[2.2]paracyclophane units, the cyclic tetramers formed either parallel‐#‐ or weave‐#‐structures. The optical and chiroptical properties of both structures were investigated experimentally and theoretically. In particular, the weave‐#‐shaped cyclic tetramer exhibited good chiroptical properties and emitted circularly polarized luminescence (CPL) with a high anisotropy factor (|glum| value of the order of 10−3) and a CPL brightness (BCPL) higher than 100. [ABSTRACT FROM AUTHOR]

Planar chiral [2.2]paracyclophane was employed as chiral scaffolds to twist an anthracene ring by tethering at its 1‐ and 8‐positions; thus, twist chirality was induced in the anthracene moiety. The chiroptical properties of the resulting molecule, including circular dichroism (CD) and circularly polarized luminescence (CPL), were found to be derived from the twist chirality. An analogous molecule bearing long alkyl chains was a viscous liquid at ambient temperature, and its liquid film exhibited good CD and CPL profiles. Theoretical studies are carried out to determine the origin of these properties in the ground and excited states, which reproduced well the experimental results. [ABSTRACT FROM AUTHOR]