Hexatertiary butyl-substituted D(3)-symmetrical cage ligands composed of octahedral bidentate complexes of Ni(II) or Cu(II) ligated on either side to triskelion arrangements of three salicyl rings bound to a central nitrogen hub atom exhibit triple-helical conformations. Maximization of intermolecular aromatic-aromatic interactions between these complexes promote extended tongue and groove interleaving and affords a supramolecular array of diastereomeric intermeshed C(3)-symmetrical triple-helices perpetuating sideways throughout alternating enantiomeric layer stacks in the entire P-3 space group crystal lattice. Chiral recognition within these supramolecular ensembles is based upon the principles of helical sense and phase. A discussion of the symmetry, mechanical and chemical factors, and constraints influencing the formation of these self-assembled crystalline supramolecular ensembles will be presented.
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http://dx.doi.org/10.1002/chir.20562 | DOI Listing |
J Am Chem Soc
January 2025
National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, Institute of Chemistry, Chinese Academy of Sciences (CAS), Beijing 100190, P. R. China.
Due to their strong aromaticity and difficulties in chemo-, regio-, and enantioselectivity control, asymmetric hydrogenation of naphthol derivatives to 1,2,3,4-tetrahydronaphthols has remained a long-standing challenge. Herein, we report the first example of homogeneous asymmetric hydrogenation of naphthol derivatives catalyzed by tethered rhodium-diamine catalysts, affording a wide array of optically pure 1,2,3,4-tetrahydronaphthols in high yields with excellent regio-, chemo-, and enantioselectivities (up to 98% yield and >99% ee). Mechanistic studies with experimental and computational approaches reveal that fluorinated solvent 1,1,1,3,3,3-hexafluoroisopropanol (HFIP) plays vital roles in the control of reactivity and selectivity, and 1-naphthol is reduced via a cascade reaction pathway, including dearomative tautomerization, 1,4-hydride addition, and 1,2-hydride addition in sequence.
View Article and Find Full Text PDFChem Rec
January 2025
Chongqing Key Laboratory of Natural Product Synthesis and Drug Research, School of Pharmaceutical Sciences, Chongqing University, Chongqing, 401331, P. R. China.
Since the introduction of the concept of inherent chirality by Böhmer, an important part of research focused on the asymmetric synthesis of calixarene macrocycles. However, long synthetic procedures and tedious separation strategies hampered the application of this technology in many topics of organic chemistry, including enantioselective molecular recognition and catalysis. Very recently, a new generation of enantioselective catalytic methodologies has been reported, able to provide highly functionalized, inherently chiral calixarenes in a straightforward manner.
View Article and Find Full Text PDFNat Mater
January 2025
Department of Electronic and Computer Engineering, The Hong Kong University of Science and Technology, Hong Kong, China.
Machine learning algorithms have proven to be effective for essential quantum computation tasks such as quantum error correction and quantum control. Efficient hardware implementation of these algorithms at cryogenic temperatures is essential. Here we utilize magnetic topological insulators as memristors (termed magnetic topological memristors) and introduce a cryogenic in-memory computing scheme based on the coexistence of a chiral edge state and a topological surface state.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2025
Institute of Chemistry Chinese Academy of Sciences, CAS Key Laboratory of Molecular Recognition and Function, CHINA.
A pair of axially chiral thermally activated delayed fluorescent (TADF) enantiomers, R-TCBN-ImEtPF6 and S-TCBN-ImEtPF6, with intrinsic ionic characteristics were efficiently synthesized by introducing imidazolium hexafluorophosphate to chiral TADF unit. The TADF imidazolium salts exhibited a high photoluminescence quantum yield (PLQY) of up to 92%, a small singlet-triplet energy gap (∆EST) of 0.04 eV, as well as reversible redox properties.
View Article and Find Full Text PDFJ Comput Chem
January 2025
Departamento de Química Fundamental, Universidade Federal de Pernambuco, Recife, Pernambuco, Brazil.
While established guidelines exist for chirality in tetrahedral molecules, there is a notable absence of clear rules for recognizing metal-centered chirality in higher-coordination complexes. We develop decision trees to assess the likelihood of chirality-at-metal in coordination complexes with coordination numbers 4-9 with mono and bidentate ligands. Using binary decision rules based on shape, ligand type, and quantity, the trees classify complexes as chiral or achiral.
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