Category Ranking
98%
Total Visits
921
Avg Visit Duration
2 minutes
Citations
20
Article Abstract
A chiral shape-persistent macrocyclic compound (Si-[3]), designed by the C/Si substitution in the spiro-atom of spirobifluorene in the cyclic trimer (C-[3]), has been successfully synthesized in this study. The C/Si substitution made the spiro-conjugation and energy levels of HOMO and LUMO decrease. Due to the silicon substitution, the macrocyclic compound Si-[3] was able to be degraded by fluoride ions, but its reaction rate was slower than that of the unsubstituted spirosilabifluorene, showing the chemical stability of Si-[3]. Furthermore, the chiroptical properties of Si-[3] with D-symmetric macrocyclic structure were investigated, and (P,P,P)-Si-[3] showed a high emission quantum yield (Φ=80 %) and moderate dissymmetry factor of circularly polarized luminescence (CPL) (g=-1.2×10). According to the time-dependent density-functional theory (TD-DFT) calculations using polarizable continuum model (PCM), the bright CPL from Si-[3] was explained by a planarization of one bisilafluorenyl moiety at the excited state, which is responsible for the almost fully-allowed radiative transition with a short emission lifetime of τ=1.89 ns.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1002/chem.202401343 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
An acetylene-bridged ferrocene macrocycle: efficient synthesis and electron transfer mechanism in mixed-valence systems.
Chem Sci
August 2025
South China Advanced Institute for Soft Matter Science and Technology, School of Emergent Soft Matter, South China University of Technology Guangzhou 510640 China
Cyclic oligomers with multiple redox centers are ideal models for intramolecular electron transfer processes, as they feature well-defined spatial geometries and degenerate energy states. The design and synthesis of such structures with strongly interacting monomers, however, remains a significant challenge. Here, we report a one-pot synthesis of an acetylene-bridged ferrocene macrocycle (9) using alkyne metathesis, with a remarkable 43% isolated yield.
View Article and Find Full Text PDFSynthesis of optically active folded cyclic dimers and trimers.
Beilstein J Org Chem
August 2025
Department of Applied Chemistry for Environment, School of Biological and Environmental Sciences, Kwansei Gakuin University, 1 Gakuen Uegahara, Sanda, Hyogo 669-1330, Japan.
Optically active higher-ordered structures, such as one-handed helical and propeller-shaped structures, can be constructed by folding the π-conjugated system using [2.2]paracyclophane as the chiral crossing unit, leading to circularly polarized luminescence (CPL) properties. Chiral cyclic dimers and trimers were synthesized using planar chiral [2.
View Article and Find Full Text PDFActivation of a Secondary-Messenger Receptor via Allosteric Modulation of a Dynamic Conformational Ensemble.
Angew Chem Int Ed Engl
August 2025
Department of Chemistry and Chemical Biology, TU Dortmund University, Otto-Hahn-Str. 4a, Dortmund, 44227, Germany.
Bacterial signaling cascades have recently become of great relevance in the context of bacterial antibiotics resistance. Cyclic diadenylate monophosphate (c-di-AMP) is a key bacterial secondary messenger involved in growth, biofilm formation, virulence gene expression and others. The activation mechanisms of c-di-AMP receptors like the trimeric P-like proteins upon messenger binding have, however, remained elusive due the pivotal role of highly flexible protein regions.
View Article and Find Full Text PDFSubstantial Effects of Ring Size on the Structure and Properties of 2,9-Anthrylene Cyclic Oligomers.
Org Lett
August 2025
Department of Chemistry, School of Science, Institute of Science Tokyo, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8551, Japan.
Cyclic oligomers consisting of unsymmetrical anthracene units were designed as novel aromatic compounds. The Suzuki-Miyaura coupling of a 2-boryl-9-bromoanthracene precursor afforded the cyclic trimer and tetramer. X-ray crystallographic analysis revealed that the trimer took a highly strained propeller-like structure with short H···H contacts.
View Article and Find Full Text PDFEnlarged-TriQuinoline (Enl-TQ): Disparity in Chemical Behaviors by Geometric Scaling of the Trimeric Quinoline Ring System.
Chem Asian J
July 2025
Graduate School of Pharmaceutical Sciences, Keio University, 1-5-30 Shibakoen, Minato-ku, Tokyo, 105-8512, Japan.
TriQuinoline (TQ), a quasi-planar cyclic quinoline trimer concatenated at the 2,8-positions in a head-to-tail arrangement, strongly captures a proton at the 12-membered inner cycle and exhibits unusual physicochemical properties, including unexpected water solubility and the ability to engage in complexation with other π-conjugated molecules. In this study, we designed and synthesized its expanded analog, coined Enlarged-TriQuinoline (Enl-TQ), in which three alkyne units are embedded between three quinoline units to acquire an expanded planar 18-membered ring system. DFT calculations and X-ray crystallographic analysis revealed its planar architecture with three inwardly facing pyridinic nitrogen atoms.
View Article and Find Full Text PDF