Aug 2026· JACS Au· Vol 6, pp. 5328 - 5335· 0 citations· 53 references
Medicine
Abstract
Herein, we report the thermodynamic locking of conformational chirality in a [9]cycloparaphenylene (CPP) by external appending of (R)- or (S)-BINOL units. Through-space steric interactions induce asymmetric torsion in the CPP backbone, generating a strained nanohoop with the lowest-energy conformer (ΔG = −2.9 kcal mol–1, corresponding to >99% population of the preferred conformer at 293 K). Temperature- and solvent-dependent circular dichroism (CD) spectra exhibit minimal signal variation, in marked contrast to conventional dynamic chiral systems and the monomeric precursor. Variable-temperature NMR reveals rapid interconversion (ΔG ‡ = 12.4 kcal mol–1), confirming fast kinetics that enable equilibration to the thermodynamically favored twisted conformation. Single-crystal X-ray diffraction and time-dependent density-functional theory (TD-DFT) calculations, including model compounds devoid of BINOL chromophores, unambiguously assign the intense Cotton effects to torsionally distorted CPP-centered π–π* transitions.
The precise transfer of chirality from a molecular scaffold to an achiral guest in solution represents a fundamental challenge, because conformational dynamics often obscure stereochemical communication. We designed two chiral ferrocene-based compounds, Fc-2Ala and Fc-3Ala, differing by one methylene in the alkyl linke...
Kun-Lin Li, Xiang-Yu Zhang, Kun Huang et al.· Nano letters (Print)· 0 citations
Chiral [2]catenanes, a prominent class of mechanically interlocked molecules (MIMs), can exhibit either static or dynamic mechanostereochemistry. Controlling these mechanostereochemical states without altering the covalent connectivity, however, remains challenging. Herein, we report a series of chiral [2]catenanes d...
Kai Lan, Rong Luo, Jin Yin et al.· Journal of the American Chem...· 0 citations
The asymmetric activation of conformationally dynamic (tropos) biaryls through covalent bond formation with stereochemically stable chiral subunits is a powerful strategy to induce a prevalent diastereomeric conformation on chiral ligands for asymmetric catalysis. This work presents an integrated computational-experime...
Giuseppe Fulvetti, Klara Mali, Filippo Lipparini et al.· Chemistry· 0 citations
A quinoline-containing cyclophane derivative with planar chirality was rationally designed and synthesized based on [2.2]paracyclophane (PCP) and used as a structural unit to induce the absolute one-handed helical conformation of quinoline foldamers. 1H NMR, X-ray crystal diffraction, and chiral HPLC studies demonstrat...
Grace Victoria Poo, Kai-Yue Liu, Yu-Ping Wu et al.· Organic Letters· 0 citations
Exact π-extension offers a molecularly precise approach for interrogating how peripheral structural modification governs the conformation, packing, and chiroptical response of atomically defined chiral nanographenes. Here we report DN-1, a naphthalene-extended chiral bilayer nanographene that reveals the regulatory rol...
Dan-Yang Wang, Nai-Te Yao, Zhi-Ao Li et al.· Chemical Science· 0 citations
We report the synthesis of two ferrocene-tethered side-chain nanohoops, Fc[8]CPP-L and Fc[8]CPP-M, via a streamlined shotgun macrocyclization protocol. Systematic variation of the tether length uncovers an interesting structure-property relationship: Fc[8]CPP-L exhibits coexisting intra- and intermolecular ferrocene in...
