The planar 3,4-diphosphinidenecyclobutene (DPCB) can be remarkably twisted into a C2 -type helical structure by dual coordination of a AuCl moiety. A prompt chirality control of the twisted DPCB skeleton ligated by the digold units affords the enantiopure structure by exchanging the chloride ligands for chiral [1,1'-binaphthalene]-2,2'-dicarboxylate. The chirality of the diaurated 2,2'-bis(diphenylphosphanyl)-1,1'-biphenyl (BIPHEP) system can be controlled prior to that of DPCB. Mixing of a DPCB-bis(chlorogold) complex with the chiral silver salt dynamically leads to a single diastereomer, which was characterized by the (31) P NMR spectrum and the CD couplet patterns in the visible (DPCB) area. The absolute configuration of the singly induced helical structure was assigned by the theoretical CD spectra determined by TD-DFT calculations. Intramolecular alkoxycyclization of hexa-4,5-dien-1-ol catalyzed by the asymmetric DPCB-digold structure were also attempted.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1002/asia.201501326 | DOI Listing |
J Am Chem Soc
January 2025
Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
Exploiting novel noncovalent interactions for catalysis design represents a fascinating direction. For the flexible and relatively weak anion-π interactions, manipulation of two or more π-acidic surfaces for cooperative activation is highly desirable. Here, we demonstrate the strategy of cooperative anion-π catalysis based on chiral molecular cages with V-shaped electron-deficient cavities for synergic binding and activation of dicarbonyl electrophiles toward highly enantioselective desymmetrization transformation.
View Article and Find Full Text PDFLight Sci Appl
January 2025
Department of Electrical and Computer Engineering, University of Delaware, Newark, Delaware, 19716, USA.
Exceptional points (EPs) have been extensively explored in mechanical, acoustic, plasmonic, and photonic systems. However, little is known about the role of EPs in tailoring the dynamic tunability of optical devices. A specific type of EPs known as chiral EPs has recently attracted much attention for controlling the flow of light and for building sensors with better responsivity.
View Article and Find Full Text PDFScience
January 2025
Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, Singapore.
Axions, hypothetical elementary particles that remain undetectable in nature, can arise as quasiparticles in three-dimensional crystals known as axion insulators. Previous implementations of axion insulators have largely been limited to two-dimensional systems, leaving their topological properties in three dimensions unexplored in experiment. Here, we realize an axion insulator in a three-dimensional photonic crystal and probe its topological properties.
View Article and Find Full Text PDFACS Nano
January 2025
College of Chemistry and Molecular Sciences, Hubei Key Laboratory of Electrochemical Power Sources, Wuhan University, Wuhan 430072, China.
Chiral plasmonic nanomaterials with fascinating physical and chemical properties show emerging chirality-dependent applications in photonics, catalysis, and sensing. The capability to precisely manipulate the plasmonic chirality in a broad spectral range plays a crucial role in enabling the applications of chiral nanomaterials in diverse and complex scenarios; however, it remains a challenge yet to be addressed. Here we demonstrate a strategy to significantly enhance the tunability of circular dichroism (CD) spectra of chiral nanomaterials by constructing core-shell hybrid metal-semiconductor structures with tailored shells.
View Article and Find Full Text PDFPest Manag Sci
January 2025
Department of Applied Chemistry, College of Science, China Agricultural University, Beijing, China.
Background: Indoxacarb, a type of chiral pesticide, is used to control Lepidoptera insects. Most studies had focused on the environmental behavior and selective toxicity of indoxacarb enantiomers, and the mechanism behind its selective biological activity against target organisms is not well understood.
Results: Spodoptera frugiperda was selected as the target insect.
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!