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Supramolecular chirality is the major branch of supramolecular chemistry, which not only plays important roles in biological processes but also in synthetically designed aggregated systems. To understand the complex processing of biological systems, the only way is to design supramolecular chiral ensembles that mimic natural biomolecules such as Deoxyribonucleic acid (DNA), Ribonucleic acid (RNA), amino acids, etc. In addition, chiral systems and self‐assemblies as molecular motifs with breaking spatial inversion symmetry have been regarded as key substances in electronics and spintronics as well as in fundamental chemistry and physics. Here, in this review, our major concern is understanding modulation in spatial arrangements and packing modes under the impact of any external stimuli, which results in tailoring the handedness of resulted supramolecular chiral superstructures. We, in this review, highlighted the role of external stimuli such as solvent, chemical additives, photo exposure, etc. in altering the supramolecular chirality for their future utility as “active switches” in optoelectronic and spintronic devices and applications. [ABSTRACT FROM AUTHOR]

This document provides a concise summary of an article discussing the synthesis and analysis of 5,7,8,10-tetraphenyl-1,14-dianilinotripyrrins. The study explores the structural changes and properties of these compounds in response to different environments and substituents. The article provides detailed information on the synthesis, structures, and spectroscopic analysis of the synthesized compounds. The findings suggest potential applications as near-infrared emitters and further research on the photophysical dynamics of tripyrrins is ongoing. The document also acknowledges funding support and provides access to additional supporting information online. [Extracted from the article]

A quasi‐planar N, N, N',N'‐tetraphenyl‐para‐phenylenediamine, where all the phenyl rings are tethered by four oxygen atoms to embed quasi‐planar triphenylamine moieties into the molecular skeleton, was prepared and characterized to evaluate the impact by incorporating the structural rigidity. The monocationic and dicationic species could be selectively generated, depending on the type of oxidizing agents used. Spectroscopic and X‐ray diffraction analyses revealed the radical cation was in a unique charge/spin delocalized class III mixed‐valence state due to an exquisite balance between the electronic effect by the oxygen‐bridges and the rigidity of molecular framework. [ABSTRACT FROM AUTHOR]

A benzannulated double aza[9]helicene 1 was successfully synthesized via a one‐pot oxidative fusion reaction. 1 was derivatized to N‐alkylated double aza[9]helicene 1‐Et and 1‐Bu, whose structures were determined by X‐ray diffraction analysis. 1‐Et and 1‐Bu exhibited red‐shifted absorption and fluorescence spectra compared to single aza[9]helicene. The double aza[9]helicenes were expected to have two different conformers. Consistent with solid‐state structure, the chiral‐isomer was estimated to be more stable by 16 kcal/mol relative to meso‐isomer. Indeed, enantiomers of 1‐Et and 1‐Bu were optically resolved by HPLC and showed mirror‐imaged CD and CPL spectra with the CPL brightness up to 19.2 M−1cm−1 for 1‐Bu. [ABSTRACT FROM AUTHOR]

Metal complexation and peripheral modifications of thiaporphyrins have been investigated for preparing polarized π-electronic cations with anion-dependent ion-pairing assembling modes, including charge-segregated structures exhibiting electric conductive properties. [ABSTRACT FROM AUTHOR]

A highly condensed packing structure with π-molecules is important to achieve high carrier transport properties. To realize condensed π-molecular arrangements, we focused on electrostatic crystal lattices consisting of cation–anion pairs and further designed an anionic N,N′-bis(ethyl sulfonate)-naphthalenediimide (ESNDI2−), which introduces structural flexibility at two –C2H4SO3− side arms. The size of the counter cation (M+) was varied from Na+, K+, Rb+, and Cs+ to design a precise crystal lattice of (M+)2(ESNDI2−)·(H2O)n salts, which is divided into hydrated salts (M+ = Na+ and K+) and anhydrous salts (M+ = K+, Rb+, and Cs+). Salt for M+ = K+ is a boundary between hydrated and anhydrous crystals, and exhibited reversible H2O adsorption–desorption behavior at 298 K. In addition, the K+ salts showed transient conductivity (φΣμ) switching behavior associated with the H2O adsorption–desorption cycle. The anhydrous salts for M+ = K+, Rb+, and Cs+ had isomorphous crystal structures, with the appearance of a two-dimensional (2D) herringbone arrangement in ESNDI2−. The condensed packing arrangement and highest φΣμ value were observed in (Rb+)2(ESNDI2−) salt. In these anhydrous salts, crystalline domains were easily formed using the simple casting method on the substrate surface. The temperature- and frequency-dependence of the dielectric constant indicated the presence of thermally induced structural fluctuations in these ionic crystal lattices. In hydrated crystals, thermal motions of Na+, K+, and H2O were dominant, whereas thermal fluctuations in the rigid M+⋯−O3S– Coulomb lattice were observed in anhydrous crystals as Debye-type relaxation. Precise structural control of the electrostatic crystal lattice determines the optimization conditions for achieving condensed π-molecular arrangement. [ABSTRACT FROM AUTHOR]

Amplified spontaneous emission (ASE) is considered to be a primary indication of optical gain in active media without an external resonator. Molecular materials with ASE are expected to be one of the suitable light sources for specific applications such as optical coherent tomography owing to their low coherence and flexible tunability. Concentration quenching of emissive excited states has been a critical issue to boost the quantum efficiency of molecular materials in their condensed phases. The rod-like design of molecules with excited state intramolecular proton transfer (ESIPT) has been demonstrated to overcome this issue in highly-concentrated molecularly-doped systems, as represented by C4alkyne-HBT (2-(4-(1-hexynyl)-2-hydroxyphenyl)-benzothiazole). We designed an ESIPT molecule-doped liquid crystalline (LC) system for optical amplification via the ASE regime with its wide tunability of emission intensity. Detailed ASE behaviour and optical gain of a LC blend of C4alkyne-HBT and 4-pentyl-4′-cyano biphenyl (5CB) was evaluated to afford a maximum optical gain of 16.5 cm−1 with an estimated ASE threshold of optical pumping at 0.6–0.7 mJ cm−2. Although most ASE studies focus on homogeneous solutions, solids, or crystalline states, ASE from a soft-flexible LC phase is quite limited and advantageous for the design of an external optical resonator/cavity structure. Optical excitation parallel and perpendicular to the director resulted in the strong modulation of the ASE. By using the benefits of a LC phase, the ASE was actively modulated under the external electric field by the reorientation of the molecular dipole moment. [ABSTRACT FROM AUTHOR]

Peripherally unsubstituted dioxadiaza[8]circulene, as the first example of structurally identified pristine hetero[8]circulene, was synthesized by the substituent detachment reactions. The solid-state structures and photophysical properties were analysed to elucidate intermolecular interactions. Herzberg-Teller type emission was considered to explain the optical behavior.

Benzo-annulated aza[9]helicene ([9]AH) and thia[9]helicene ([9]TH) were prepared as novel π-extended heterohelicenes. [9]TH showed a quite short fluorescence lifetime of ∼0.3 ns and intense phosphorescence at low temperature that were attributed to its larger spin-orbit coupling and faster intersystem crossing between pseudo-degenerate S 1/2 and triplet states., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Significant effort has been devoted to the development of materials that combine high electrical conductivity and permanent porosity. This paper discloses a diazaporphyrin-based hydrogen-bonded organic framework (HOF) with porosity and n-type semiconductivity. A 5,15-diazaporphyrin Ni(ii) complex with carboxyphenyl groups at the meso positions afforded a HOF due to hydrogen-bonding interactions between the carboxy groups and meso -nitrogen atoms. The thermal and chemical stabilities of the HOF were examined using powder X-ray diffraction analysis, and the charge-carrier mobility was determined to be 2.0 × 10 -7 m 2 V -1 s -1 using the flash-photolysis time-resolved microwave conductivity (FP-TRMC) method. An analogous diazaporphyrin, which does not form a HOF, exhibited mobility that was 20 times lower. The results presented herein highlight the crucial role of hydrogen-bonding networks in achieving conductive pathways that can tolerate thermal perturbation., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Synthetic challenges toward anomalous structures and electronic states often involve handling problems such as insolubility in common organic solvents and oxidative degradation under aerobic conditions. We designed benzo-annulated aza[ n ]helicenes, which benefit from both the suppressed elevation of highest occupied molecular orbital (HOMO) energies and high solubility due to hydrogen bonding with solvent molecules to overcome these challenges. This strategy enabled the synthesis of six new aza[ n ]helicenes ( [ n ]AH s) of different lengths ( n = 9-19) from acyclic precursors via one-pot intramolecular oxidative fusion reactions. The structures of all of the synthesized aza[ n ]helicenes were determined by X-ray diffraction (XRD) analysis, and their electrochemical potentials were measured by cyclic voltammetry. Among the synthesized aza[ n ]helicenes, [17]AH and [19]AH are the first heterohelicenes with a triple-layered helix. The noncovalent interaction (NCI) plots confirm the existence of an effective π-π interaction between the layers. The absorption and fluorescence spectra red-shifted as the helical lengths increased, without any distinct saturation points. The optical resolutions of N -butylated [9]AH , [11]AH , [13]AH , and [15]AH were accomplished, and their circular dichroism (CD) and circularly polarized luminescence (CPL) were measured. Thus, the structural, (chir)optical, and electrochemical properties of the aza[ n ]helicenes were comprehensively analyzed.

Background: Older adults with acute myocardial infarction (AMI) are currently a rapidly growing population. However, their clinical presentation and outcomes remain unresolved. Methods and Results: A total of 268 consecutive AMI patients were analyzed for clinical characteristics and outcomes with major adverse cardiovascular events (MACE) and all-cause mortality within 1 year. Patients aged ≥80 years (Over-80; n=100) were compared with those aged ≤79 years (Under-79; n=168). (1) Primary percutaneous coronary intervention (PCI) was frequently and similarly performed in both the Over-80 group and the Under-79 group (86% vs. 89%; P=0.52). (2) Killip class III-IV (P<0.01), in-hospital mortality (P<0.01), MACE (P=0.03) and all-cause mortality (P<0.01) were more prevalent in the Over-80 group than in the Under-79 group. (3) In the Over-80 group, frail patients showed a significantly worse clinical outcome compared with non-frail patients. (4) Multivariate analysis revealed Killip class III-IV was associated with MACE (odds ratio [OR]=3.51; P=0.02) and all-cause mortality (OR=9.49; P<0.01) in the Over-80 group. PCI was inversely associated with all-cause mortality (OR=0.13; P=0.02) in the Over-80 group. Conclusions: The rate of primary PCI did not decline with age. Although octogenarians/nonagenarians showed more severe clinical presentation and worse short-term outcomes compared with younger patients, particularly in those with frailty, the prognosis may be improved by early invasive strategy even in these very old patients., Competing Interests: All authors have no conflicts of interest to disclose., (Copyright © 2024, THE JAPANESE CIRCULATION SOCIETYCopyright © 2024, THE JAPANESE CIRCULATION SOCIETY.)

A benzannulated double aza[9]helicene 1 was successfully synthesized via a one-pot oxidative fusion reaction. 1 was derivatized to N-alkylated double aza[9]helicene 1-Et and 1-Bu, whose structures were determined by X-ray diffraction analysis. 1-Et and 1-Bu exhibited red-shifted absorption and fluorescence spectra compared to single aza[9]helicene. The double aza[9]helicenes were expected to have two different conformers. Consistent with solid-state structure, the chiral-isomer was estimated to be more stable by 16 kcal/mol relative to meso-isomer. Indeed, enantiomers of 1-Et and 1-Bu were optically resolved by HPLC and showed mirror-imaged CD and CPL spectra with the CPL brightness up to 19.2 M -1 cm -1 for 1-Bu., (© 2024 Wiley-VCH GmbH.)

Supramolecular electronics exploits the distinctive features stemming from noncovalent interactions, guiding the self-assembly of molecules to craft materials endowed with customized electronic functionalities. Hydrogen-bonded materials, characterized by their capacity to establish dynamic and stable networks, introduce an extra dimension to the development of supramolecular electronic systems. This study presents a comparative analysis of two remarkably small semiconductors utilizing diketopyrrolopyrrole functionalized with urea units as hydrogen-bonding motifs, strategically positioned at opposing ends of the conjugated core. We show how the subtle distinction in functionalization not only influences morphology and self-assembly dynamics via hydrogen-bonding and π-π stacking formation, but also holds significant consequences for ultimate charge transport properties. Our observations into the interplay of noncovalent interactions provide valuable insights and strategic pathways for the design of novel materials with enhanced electronic characteristics., (© 2024 Wiley-VCH GmbH.)