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Chiral organic molecules possessing high quantum yields, circular dichroism, and circularly polarized luminescence values have great potential as optically active materials for future applications. Recently, the identification of a promising class of inherently chiral compounds was reported, namely macrocyclic 1,3‐butadiyne‐linked pseudo‐meta[2.2]paracyclophanes, displaying high circular dichroism and related gabs values albeit modest quantum yields. Increasing the quantum yields in an attempt to get bright circularly polarized light emitters, the high‐yielding heterocyclization of those 1,3‐butadiyne bridges resulting in macrocyclic 2,5‐thienyls‐linked pseudo‐meta [2.2]paracyclophanes is herein described. The chiroptical properties of both, the previously reported 1,3‐butadiyne, and the novel 2,5‐thienyl bridged macrocycles of various sizes, are experimentally recorded, and theoretically described using density‐functional theory. [ABSTRACT FROM AUTHOR]

Orthogonal joints, understood as connections with an angle of 90°, were introduced in the design of the "Geländer" model compounds 1 and 2. The banister, consisting of a conjugated carbazole dimer linked by either 1,3‐butadiyne (2) or a single thiophene (1), wraps around an axis composed of a phthalimide dimer due to the dimensional mismatch of both subunits, which are interconnected by phenylene rungs. The "Geländer" structure was assembled from a monomer comprising the 1,4‐diaminobenzene rung with one amino substituent as part of a 4‐bromo phthalimide subunit forming the orthogonal junction to the axis, and the other as part of a masked 2‐ethynyl carbazole as orthogonal joint to the banister. The macrocycle was obtained by two sequential homocoupling steps. A first dimerization by a reductive homocoupling assembled the axis, while an oxidative acetylene coupling served as ring‐closing reaction. The formed butadiyne was further derivatized to a thiophene, rendering all carbons of the model compound sp2 hybridized. Both helical structures were fully characterized and chirally resolved. Assignment of the enantiomers was achieved by simulation of chiroptical properties and enantiopure synthesis. [ABSTRACT FROM AUTHOR]

The synthetic access to macrocyclic molecular topologies with interesting photophysical properties has greatly improved thanks to the successful implementation of organic and inorganic corner units. Based on recent reports, we realized that pseudo‐meta [2.2]paracyclophanes (PCPs) might serve as optimal corner units for constructing 3D functional materials, owing to their efficient electronic communication, angled substituents and planar chirality. Herein, we report the synthesis, characterization and optical properties of four novel all‐carbon enantiopure macrocycles bearing three to six pseudo‐meta PCPs linked by 1,3‐butadiyne units. The macrocycles were obtained by a single step from enantiopure, literature‐known dialkyne pseudo‐meta PCP and were unambiguously identified and characterized by state of the art spectroscopic methods and in part even by x‐ray crystallography. By comparing the optical properties to relevant reference compounds, it is shown that the pseudo‐meta PCP subunit effectively elongates the conjugated system throughout the macrocyclic backbone, such that already the smallest macrocycle consisting of only three subunits reaches a polymer‐like conjugation length. Additionally, it is shown that the chiral pseudo‐meta PCPs induce a remarkable chiroptical response in the respective macrocycles, reaching unprecedented high molar circular dichroism values for all‐carbon macrocycles of up to 1307 L mol−1 cm−1. [ABSTRACT FROM AUTHOR]

A 3D porous perchlorinated metal-organic framework (MOF), LIFM-26, featuring dual functionality, that is, functional polar groups and open metal sites, has been synthesized using perchlorinated linear dicarboxylate to link trigonal prismatic Fe3(μ3-O) units. LIFM-26 exhibits good thermal and chemical stability, and possesses high porosity with a BET surface area of 1513 m2 g−1, compared with isoreticular MOF-235 and Fe3O(F4BDC)3(H2O)3 (F4BDC=2,3,5,6-tetrafluorobenzene-1,4-dicarboxylate). Most strikingly, LIFM-26 features good gas sorption/separation performance at 298 K and 1 atm with IAST selectivity values reaching up to 36, 93, 23, 11, 46, and 202 for CO2/CH4, CO2/N2, C2H4/CH4, C2H6/CH4, C3H8/CH4, and R22/N2 (R22=CHClF2), respectively, showing potential for use in biogas/natural gas purification and CO2/R22 capture. [ABSTRACT FROM AUTHOR]

Two analogous M4L4-type tetrahedral cages (smaller: MOC-19; larger: MOC-22) were synthesized and investigated for their interactions with the anticancer drug 5-fluoracil (5-FU) by NMR spectroscopy, high-resolution electrospray-ionization mass spectrometry (HR-ESI-MS), and molecular simulation. The cage's size and window are of importance for the host-guest binding, and consequently the smaller MOC-19 with a more suitable size of cavity window was found to have much stronger hydrogen-bond interactions with 5-FU. The porous nanoparticles of MOC-19 exhibited outstanding behavior for the controlled release of 5-FU in a simulated human body with liquid phosphate-buffered saline solution. [ABSTRACT FROM AUTHOR]

Front Cover: Intense Molar Circular Dichroism in Fully Conjugated All-Carbon Macrocyclic 1,3-Butadiyne Linked pseudo-meta [2.2]Paracyclophanes (Chem. Eur. J. 53/2022) The angle and flexibility of the pseudo- I meta i substituents enabled high yielding macrocyclization reactions, and the studied trimeric, tetrameric, pentameric and hexameric structures further displayed astonishing through-space polymer-like conjugation lengths. Keywords: [2.2]paracyclophane; hydrocarbon; macrocycle; molar circular dichroism; -conjugation EN [2.2]paracyclophane hydrocarbon macrocycle molar circular dichroism -conjugation 1 1 1 09/27/22 20220922 NES 220922 B Unprecedented high molar circular b dichroism values for all-carbon macrocycles were revealed in 1,3-butadiyne bridged pseudo- I meta- i [2.2]paracyclophanes. [Extracted from the article]

The silver salts of 1-adamantanethiol (AdSH) and furan-2-ylmethanethiol (FurCH2SH) were successfully applied as building blocks for ligand-protected Ag2S nanoclusters. The reaction of the silver thiolates [AgSAd]x and [AgSCH2Fur]x with S(SiMe3)2 and 1,5-bis(diphenylphosphino) pentane (dpppt) afforded three different clusters with 58, 94 and, 190 silver atoms. The intensely colored compounds [Ag58S13(SAd)32] (1), [Ag94S34(SAd)26(dpppt)6] (2), and [Ag190S58(SCH2Fur)74(dpppt)8] (3) were structurally characterized by single-crystal X-ray diffraction and exhibit different cluster core geometries and ligand shells. The diameters of the well-defined sphere-shaped nanoclusters range from 2.2 nm to 3.5 nm. [ABSTRACT FROM AUTHOR]

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