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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]

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 [...]

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]

Herein, we report the synthesis and chiroptical properties of 2-azatriptycenes and their platinum(II) complexes, which represent the first examples of heterotriptycenes and metallotriptycenes that exhibit circularly polarized fluorescence and phosphorescence (CPF and CPP). Theoretical studies for CPF and CPP strongly support the experimental findings. [ABSTRACT FROM AUTHOR]

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]

Optical resolution of pseudo-para-disubstituted [2.2]paracyclophane was achieved using the diastereomer method. Optically active π-stacked molecules consisting of phenanthrene and benzo[c]phenanthrene were synthesized using the enantiopure pseudo-para-disubstituted [2.2]paracyclophanes as chiral building blocks. Helicity was induced on the stacked phenanthrene and benzo[c]phenanthrene moieties by the planar chiral [2.2]paracyclophane, and the molecule formed an optically active S-shaped structure. The S-shaped molecule emitted circularly polarized luminescence, which was compared with that of the corresponding optically active U-shaped molecule prepared from pseudo-meta-disubstituted [2.2]paracyclophane. [ABSTRACT FROM AUTHOR]

Herein, we report the synthesis, crystal structure, and optical properties of a heterotriptycene consisting of an unsubstituted bispyrrole, 2,4,6,8‐tetrahydro‐4,8‐benzobenzo[1,2‐c:4,5‐c′]dipyrrole, which was synthesized via hetero‐Diels‐Alder reaction of a novel benzobicyclo[2.2.2]octane derivative. The compound formed a 2D nested hexagonal array with NH⋅⋅⋅π interactions in the crystalline state; whereas, in the solution state, it exhibited through‐space intramolecular charge transfer (ICT) induced emission in the solution state. [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]

Optically active cyclic dimer, trimer, and tetramer, in which the p‐arylene‐ethynylenes were stacked, were prepared using enantiopure 4,7,12,15‐tetrasubstituted [2.2]paracyclophane as the chiral building block. All molecules exhibited clear Cotton effects in their absorption bands with mirror image spectra, and the signals of the longest wavelengths of the (Rp)‐ and (Sp)‐isomers were positive and negative, respectively. Their circularly polarized luminescence (CPL) signs corresponded with the those of the first Cotton effect. For all molecules, molecular orbitals were localized in one of the stacked p‐arylene‐ethynylenes in the excited states, resulting in a similar photoluminescence behavior. Although the cyclic dimer did not emit CPL, the cyclic trimer and tetramer exhibited intense CPL emissions with a relatively high dissymmetry factor in the order of 10−3. Their optical and chiroptical properties were reproduced by time‐dependent density functional theory calculations. [ABSTRACT FROM AUTHOR]

Two optically active molecules were prepared using enantiopure planar chiral [2.2]paracyclophane as chiral building blocks, in which π‐electron systems were stacked at 120° to form a V‐shaped structure. The optical and chiroptical properties of the synthesized molecules were investigated experimentally and theoretically. The chiroptical properties depended strongly on the orientation of the stacked π‐electron systems; in other words, these properties could be regulated by changing the orientation of the stacked π‐electron systems. [ABSTRACT FROM AUTHOR]

The yields of mono- and di-alkylated amines vary with the type of ruthenium complexes used as catalysts during the N-alkylation of heteroaromatic amines with alcohols. 2-aminopyridine reacts with excess of ethanol at 180 degrees celsius for 20 hours to give 9% 2-(ethylamino)pyridine (1) and 70% 2-(diethylamino)pyridine with dichlorotris(triphenylphosphine)ruthenium as catalyst. The use of (eta(super 4)-1,5-cyclooctadiene)(eta(super 6)-1,3,5-cyclooctatriene)ruthenium as catalyst forms 85% of 1 even in excess of ethanol. The use of tertiary phosphines and phosphites increases the dialkylated form.

Two kinds of optically active V‐shaped molecules were synthesized from enantiopure disubstituted and tetrasubstituted [2.2]paracyclophane as chiral building blocks. The p‐arylene‐ethynylene‐type π‐electron systems in these species were stacked at an angle of 60°, and although the two molecules consisted of the same π‐electron system, the orientations of these systems were different. In addition, their optical properties were almost identical, while in contrast, significant differences were observed between their chiroptical properties. It was therefore suggested that circularly polarized luminescence behavior could be controlled by adjusting the orientation of the stacked π‐electron systems. [ABSTRACT FROM AUTHOR]

Optically active conjugated molecules bearing one-handed helical structures, in which two [4]helicenes or two phenanthrenes are stacked at terminal benzene moieties, were prepared using enantiopure [2.2]paracyclophane as a chiral scaffold. The obtained molecules exhibited excellent chiroptical properties such as circularly polarized luminescence with high disymmetry factors. Planar chiral pseudo-meta-disubstituted [2.2]paracyclophane was also optically resolved on the sub-gram-scale. [ABSTRACT FROM AUTHOR]

An optically active binuclear platinum(II) complex based on planar chiral [2.2]paracyclophane was synthesized. The corresponding enantiomers exhibited red circularly polarized phosphorescence (CPP) with the dissymmetry factor ‖glum‖ = 1.0 × 10−3. We report, for the first time, theoretical estimation of the CPP ‖glum‖ value using relativistic calculations. [ABSTRACT FROM AUTHOR]

Optically active X‐shaped molecules based on the planar chiral [2.2]paracyclophane building block were prepared, in which di(methoxy)terphenyl units were stacked on the central benzene rings. At 25 °C, anisolyl rings freely rotate in solution, while in the crystal form, they are fixed by intramolecular CH–π interactions, thereby leading to the expression of the axial chirality, i.e. propeller chirality was exhibited by the planar chiral [2.2]paracyclophane moiety. The X‐shaped molecule exhibited good circularly polarized luminescence (CPL) profiles with moderate ΦPL and a large glum value in the order of 10−3 at 25 °C, in solution. In contrast, at −120 °C, dual CPL emission with opposite signs was observed. According to the theoretical studies, the rotary motion of the anisolyl units is suppressed in the excited states, and so emission from two isomers could be observed. These results demonstrate that the axial chirality was controlled by the planar chirality, leading ultimately to propeller chirality. [ABSTRACT FROM AUTHOR]

Heteroleptic platinum(II) complexes find wide application in supramolecular and photochemistry. Nevertheless, efficient methods for their preparation are limited. Herein, we report a novel synthetic approach toward heteroleptic trans‐bis(iminopyrrolyl)Pt(II) complexes with N‐propyl, ‐pentyl, ‐methoxyethyl, and ‐phenyl substituents using a Zeise's dimer analog as the platinum source. The developed route, which consists of two sequential complexation reactions with the corresponding sodium salt of the iminopyrrolyl ligand, is operationally simple and delivered the mono and trans‐bis coordinated products quantitatively and highly stereoselectively. The obtained Pt(II) complexes exhibited crystallization‐induced phosphorescent emission enhancement behavior. Furthermore, the luminescence properties were dependent on the substituents on the nitrogen atoms of the iminopyrrolyl ligands. Hence, this study is expected to have important implications in the fields of supramolecular and photochemistry. [ABSTRACT FROM AUTHOR]

One-pot synthesis of functionalized polyynes and derivatization of di- and triynes is developed based on a Fritsch-Buttenberg-Wiechell (FBW) rearrangement-deprotonation sequence. The lithium acetylide formation the FBW reaction has undergone transmetalation for providing the corresponding zinc, copper, tin or platinum acetylides, thus leading to the divergent formation of symmetrical and unsymmetrical conjugated acetylenes, as well as ynones.

Planar chiral building blocks based on 4,7,12,15‐tetrasubstituted [2.2]paracyclophanes were obtained via a synthetic route involving an optical resolution step. Planar chiral enantiomers, comprising two fluorophores that were stacked to form a V‐shaped higher‐ordered structure, were synthesized from these building blocks. The V‐shaped molecules emitted intense circularly polarized luminescence (CPL). Their chiroptical properties were compared with those of X‐shaped molecules bearing the same two fluorophores stacked together. The CPL sign of the X‐shaped molecule was opposite to that of the V‐shaped molecule, which is supported by the theoretical results, indicating that the CPL sign can be controlled by the orientation of the stacked fluorophores. [ABSTRACT FROM AUTHOR]

To obtain solid‐state emissive materials having stimuli‐responsive luminescent chromic properties without phase transition, benzobithiophenes modified with two o‐carborane units having various substituents in the adjacent phenyl ring in o‐carborane were designed and synthesized. Their emission colors were strongly affected not only by the substituents at the para‐position of the phenyl ring but also by molecular distribution in the solid state. In particular, the emission colors were changed by heating without crystal phase transition. It was proposed that their thermochromic properties were correlated not with isomerization but with the molecular motion at the distorted benzobithiophene moiety. Bright crystals: A series of benzobithiophenes modified with two ortho‐carborane units having various substituents were synthesized. It was found that their emission colors were strongly affected by molecular distribution in the solid state as well as by the substituents at the para‐position of the phenyl ring. Particularly, the emission colors were rapidly changed by heating without crystal phase transition. [ABSTRACT FROM AUTHOR]

Simple and readily available ruthenium complexes of the type CpRuCIL(sub 2) are found to act as efficient catalysts for the synthesis of propargylic sulfides through S-propargylation of aromatic or aliphatic thiols under neutral conditions. This reaction may complement the previously reported thiolate-bridged diruthenium complex-catalyzed S-propargylation of thiols with terminal propargylic alcohols.