Article
Chemistry, Organic
Naoyuki Hisano, Takeharu Haino
Summary: The host-guest complexation between a bisporphyrin cleft and electron-deficient guest molecules was studied. The X-ray crystal structures showed that the guest molecules were located within the cleft and formed pi-pi stacking interactions. Binding constants and thermodynamic parameters were determined using isothermal titration calorimetry. Two types of enthalpy-entropy compensation effects were observed based on the guest's movement within the cleft. Chiral guest encapsulation induced bisignate circular dichroism.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Physical
Li Yang, Xiaoqiu Dou, Chunmei Ding, Chuanliang Feng
Summary: In supramolecular assemblies, the emergence, transference, amplification, and memory of chiroptical activity, including circularly polarized absorbance and circularly polarized luminescence, remain significant challenges. By using hydrogen-bonding interactions, achiral and chiral components can coassemble into helical nanostructures with fine chiroptical activity, which can be remembered in the assemblies even after the removal of chiral additives. The removed chiral elements can be reused to achieve continuous circulation and amplification of chirality in a supramolecular assembly system, providing insight into potential applications in the manufacturing of chiroptical materials.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2021)
Article
Chemistry, Inorganic & Nuclear
Bapan Saha, Dolly Chandel, Sankar Prasad Rath
Summary: The rationalization for chirality transfer mechanism in supramolecular host-guest assemblies has been reported for the first time. The cyclic dimer displays a large bisignate CD couplet, while the monomeric complexes exhibit negligible CD intensity. Crystallographic characterizations demonstrate that the strong intermolecular H bonding in cyclic dimers is responsible for their stability over the linear chain.
INORGANIC CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Kentaro Harada, Ryo Sekiya, Takeharu Haino
Summary: By utilizing a confined space, we have achieved the formation of trimeric structures composed of acetic acid and tartaric acid derivatives, with transfer and enrichment of chirality. The generated capsule guides the dynamic axial chirality and enables the emission of circularly polarized luminescence in the NIR region.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Sylwia Parzyszek, Jacopo Tessarolo, Adrian Pedrazo-Tardaos, Ana M. Ortuno, Maciej Baginski, Sara Bals, Guido H. Clever, Wiktor Lewandowski
Summary: This study proposes a strategy to achieve strongly dissymetric CPL in nanocomposite films based on chiroptical induction and energy transfer to semiconductor nanocrystals. By controlling the chirality of helical nanofilaments in liquid crystal matrix and adjusting energy transfer from organic films to quantum dots, CPL wavelengths can be conveniently tuned. This approach provides a simple and versatile method to modulate the CPL activity of organic materials.
Article
Nanoscience & Nanotechnology
Lifei Xu, Mingming Zhang, Xuefeng Zhu, Chenlu Xue, Han-Xiao Wang, Minghua Liu
Summary: This study found that amphiphiles self-assembled into different chiral nanomaterials in different solvents, showing opposite handedness and modulation of energy transfer efficiency.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Chemistry, Multidisciplinary
Xin Zhang, Haoxuan Ding, Shu Yang, Hualin Yang, Xiaoqing Yang, Bosheng Li, Xueting Xing, Yaojie Sun, Guangxin Gu, Xiaorui Chen, Jianzhi Gao, Minghu Pan, Lifeng Chi, Quanmin Guo
Summary: Chirality transfer plays a vital role in the structure and functionality of biological systems. By adjusting the kinetic factors, such as deposition rate and heat treatment, different chiral 2D assemblies can be synthesized on the Au(111) surface from achiral molecules, resulting in enantiomeric entities. The results demonstrate that chirality transfer and induction in biological assemblies can be controlled by altering the kinetic factors, providing insights and practical approaches for the design of complex biomolecular superstructures.
Article
Polymer Science
Xiao-Xiao Cheng, Teng-Fei Miao, Lu Yin, Wei Zhang, Xiu-Lin Zhu
Summary: Chirality is widely present in nature and organisms, especially studied in chemistry and biomedical science. The demand for constructing chiral polymers has been rapidly growing, but current methods are often tedious and expensive. Certain chirality induction strategies are considered highly versatile and efficient in producing chirality from achiral polymers.
CHINESE JOURNAL OF POLYMER SCIENCE
(2021)
Article
Chemistry, Multidisciplinary
Bowen Shen, Chunyu Pan, Xiaopeng Feng, Jehan Kim, Mo Sun, Myongsoo Lee
Summary: Researchers report spontaneous chirality induction in a single layer 2D network structure formed from the self-assembly of tetrapod azobenzene molecules. The chirality induction occurs due to the slipping of multiple sublayers in a preferred direction, where the sublayer consists of different molecular arrangements in the in-plane a and b directions, breaking both the plane of symmetry and inversion symmetry. The protruded azobenzene units in the pore interior can be selectively isomerized upon UV irradiation, resulting in a reversible deformation of the chiral pores while maintaining the 2D frameworks. The chiral network can selectively trap one enantiomer from a racemic solution and release it upon UV irradiation.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Yawen Li, Qingfang Li, Xiaran Miao, Chunyan Qin, Dake Chu, Liping Cao
Summary: Achiral supramolecular organic framework (SOF-1) can exhibit adaptive chirality induced by specific compounds in water, leading to mirror-image circular dichroism and circularly polarized luminescence. This adaptive chirality can be utilized for determining the enantiopurity of amino acids and distinguishing biological chiral macromolecules.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Multidisciplinary
Han Wu, Xin He, Biao Yang, Cui-Cui Li, Liang Zhao
Summary: The study involved constructing spirocyclic Ag-9 clusters by vertex-sharing of in-situ-generated heteroaryl diide-centered metal rings, demonstrating versatile photoluminescent and chiroptical behavior. Under different aggregation conditions, assembly led to cluster-based phosphorous luminescence and micrometer-long helical nanofibers. Exciton couplings of chelating ligands at molecular and microscopic levels in the assembled film of cluster enantiomers resulted in circularly polarized luminescence with a high anisotropy factor (0.16).
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Multidisciplinary
Qiuhong Cheng, Aiyou Hao, Pengyao Xing
Summary: In this study, supramolecular chirality in deep eutectic solvents (DESs) was explored, leading to the fabrication of functional soft chiral self-assemblies with controllable chiroptical properties.
Article
Chemistry, Multidisciplinary
Masayuki Morie, Ryo Sekiya, Takeharu Haino
Summary: A water-soluble triply stranded metallohelicate capable of incorporating small molecular cations was studied. It was found that some cations exhibit positive cooperativity in host-guest complexation, while others show noncooperativity. Density functional theory calculations revealed that the conformation of the helicate cavity changes upon encapsulation of the first guest, which in turn affects the binding of the second guest. Circular dichroism spectroscopy showed that the chirality of the guests can be transmitted to the helicate, and the CD intensity is nonlinear with the enantiomeric excess of the guests.
CHEMISTRY-AN ASIAN JOURNAL
(2022)
Article
Chemistry, Multidisciplinary
Ganyin Yuan, Chu Wang, Zheng Xi, Shixin Li, Xiaohuan Sun, Pengyuan Hang, Xu Liu, Jie Han, Rong Guo
Summary: Understanding the origin of asymmetric information on chiral nanozymes is crucial for enantioselective catalysis. In this study, supramolecular chiral nanozymes composed of P/M-polyaniline (P/M-PANI) nanotwists and metal ions (M2+, M = Cu, Ni, Co, and Zn) were designed using thioglycolic acid (TA) without chiral molecules, resulting in regulated catalytic efficiency and enantioselectivity. The P-PANI-TA-M2+ nanozymes showed preference for 3,4-dihydroxy-S-phenylalanine (S-DOPA) oxidation, while M-PANI-TA-M2+ exhibited better selectivity for R-DOPA oxidation. Among them, Co2+-doped nanotwists showed the best enantioselectivity with a selectivity factor as high as 2.07. Molecular dynamics (MD) simulation elucidated the mechanism of enantioselective catalysis due to differential kinetics between S/R-DOPA enantiomers adsorbed on chiral PANI surface and free in solution. This work provides deep understanding of asymmetric catalysis and serves as a strong foundation for designing nanozymes with high enantioselectivity.
Article
Chemistry, Multidisciplinary
Marius Morgenroth, Mirko Scholz, Laure Guy, Kawon Oum, Thomas Lenzer
Summary: We have observed efficient induction of chirality in polyfluorene copolymer thin films by mixing with helicene-type chiral additives based on the dibenzo[c,h]acridine motif. Circular dichroism (CD) and circularly polarized luminescence (CPL) microscopy provide information about the chiral arrangements in the thin films. The CD signal shows a characteristic dependence on the film thickness, supporting a supramolecular origin of the strong chiral response.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Review
Chemistry, Multidisciplinary
Luis Escobar, Qingqing Sun, Pablo Ballester
Summary: Proteins possess high-binding affinity and selectivity, as well as remarkable catalytic performance. Synthetic receptors with sizable aromatic cavities and converging polar groups have received considerable attention.
ACCOUNTS OF CHEMICAL RESEARCH
(2023)
Review
Chemistry, Multidisciplinary
Sayan Sarkar, Pablo Ballester, Mark Spektor, Evgeny A. Kataev
Summary: The design of high-affinity synthetic host-guest complexes is crucial for constructing novel supramolecular assemblies, functional materials, molecular probes, artificial signal transduction events, and interfaces with the biological world. This review discusses recent achievements in designing 1:1 host-guest complexes with exceptional stabilities exceeding 10(6) M-1. The relationships between thermodynamic constants and structural parameters are analyzed, and the design features of high-affinity hosts are discussed, considering different solvents and noncovalent interactions for complex stabilization. Hints for future design of synthetic receptors with high affinity and selectivity are provided.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Andrea Rivoli, Rosa M. Gomila, Antonio Frontera, Pablo Ballester
Summary: This study reports the synthesis and X-ray structures of three alpha,beta two wall aryl-extended calix[4]pyrroles with either identical or different meso-aryl substituents. The solid-state structures of the compounds show a 1,3-alternate conformation and the presence of co-crystallized acetonitrile solvent molecules. The non-symmetrically substituted compound exhibits inherent chirality and a head-to-tail directional disorder due to the functional complementarity of the para-substituents.
CHEMISTRY-AN ASIAN JOURNAL
(2023)
Article
Nanoscience & Nanotechnology
Beatriu Domingo-Tafalla, Tamal Chatterjee, Federico Franco, Javier Perez Hernandez, Eugenia Martinez-Ferrero, Pablo Ballester, Emilio Palomares
Summary: Electro- and photoinduced charge transfer in nanocrystalline mesoporous TiO2 film and TiO2/iron porphyrin hybrid films under CO2 reduction conditions were studied. The TiO2 film exhibited a reduction in the absorption and lifetime of photogenerated electrons under laser excitation and applied voltage. The TiO2/iron porphyrin films showed faster charge recombination kinetics and exclusive formation of CO during CO2 reduction. The competitive processes between oxidized iron porphyrin and TiO2 conduction band electrons were identified as the reason for the moderate performances of the hybrid films.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Review
Chemistry, Multidisciplinary
Gemma Aragay, Pablo Ballester
Summary: The study of molecular recognition processes in water using biomimetic synthetic receptors provides valuable information for understanding more complex biological processes. In this study, we focused on the use of aryl-extended calix[4]pyrrole (AE-C[4]P) scaffolds for binding small polar molecules in water. The results show that AE-C[4]Ps can be considered as simple biomimetic analogs of enzyme binding sites.
ISRAEL JOURNAL OF CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Kuppusamy Kanagaraj, Rui Wang, Ming-Kai Zhao, Pablo Ballester, Julius Rebek Jr, Yang Yu
Summary: A series of alkyl-O-methyl aldoximes with various functional groups were synthesized and showed E-Z isomerization in organic solutions. However, these compounds exhibited high selectivity for the cis-Z isomer when confined in a water-soluble capsule. The affinities for the chalcogen-bonded capsule depended on the guest chain length and functional groups. An E-to-Z isomer selectivity of >99% was achieved with a chain length of 14 heavy atoms, and the isomerization was accelerated by sonication.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Inorganic & Nuclear
Andres F. Sierra, Evgeny Bulatov, Gemma Aragay, Pablo Ballester
Summary: We report the synthesis and characterization of two diastereomeric phosphoramidite calix[4]pyrrole cavitands and their corresponding gold(I) complexes. The catalytic activity of these complexes in the hydration reaction of propargyl esters was studied. The presence of polar hydrogen bond acceptor groups in the substrate was found to decrease the hydration rate constants, possibly due to coordination competition with the Au(I) metal center of the catalysts.
INORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Enric Petrus, Diego Garay-Ruiz, Markus Reiher, Carles Bo
Summary: In this study, a unique computational approach was used to successfully simulate the self-assembly processes of metal-oxide nanoclusters. By estimating activation energies and correcting pK (a) values, multi-time-scale kinetic simulations were conducted, reproducing reactions ranging from tens of femtoseconds to months of reaction time. Analysis of the kinetic data and reaction network topology revealed the details of the main reaction mechanisms, explaining the origin of kinetic and thermodynamic control. Simulations at alkaline pH fully reproduced experimental evidence as clusters did not form under those conditions.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Inorganic & Nuclear
Diego Jaraba Cabrera, Ryan D. Lewis, Carlos Diez-Poza, Lucia Alvarez-Miguel, Marta E. G. Mosquera, Alex Hamilton, Christopher J. Whiteoak
Summary: This study investigates the synthesis of aluminum, gallium, and indium compounds supported by a readily prepared salphen ligand and explores their structures and potential as catalysts for the synthesis of cyclic carbonates. It is demonstrated that the indium compounds are the most active catalysts, despite their lower Lewis acidity compared to aluminum compounds. A Density Functional Theory (DFT) study provides important insights into the reasons for the high activity of the indium catalyst.
DALTON TRANSACTIONS
(2023)
Article
Chemistry, Inorganic & Nuclear
Naoyuki Hisano, Virginia Valderrey, Gemma Aragay, Pablo Ballester
Summary: We report the self-assembly of a di-nuclear tetralactam macrocyle based on two symmetric components and investigate its binding properties with adipamide derivatives. We observe the formation of a weakly bound 1:1 complex with linear alkyl chains and a preferred binding geometry of [2]pseudorotaxane topology. In the presence of bulky stoppers, two different complexes are formed, with the second complex displaying slow exchange kinetics and a [2]rotaxane topology.
DALTON TRANSACTIONS
(2023)
Article
Chemistry, Multidisciplinary
Gloria Tobajas-Curiel, Qingqing Sun, Jeremy K. M. Sanders, Pablo Ballester, Christopher A. Hunter
Summary: Molecular recognition in water involves various factors such as polar functional group interactions, desolvation of polar and non-polar surfaces, and changes in conformational flexibility. Supramolecular complexes that can be studied in both water and non-polar solvents are used to dissect the effects of substituents on aromatic interactions. The study reveals that H-bonding interactions and aromatic interactions contribute significantly to the stability of the complex, with substituents further enhancing the stability.
Article
Chemistry, Multidisciplinary
Nanako Tamai, Naoki Ogiwara, Eri Hayashi, Keigo Kamata, Toshiyuki Misawa, Takeru Ito, Tatsuhiro Kojima, Mireia Segado, Enric Petrus, Carles Bo, Sayaka Uchida
Summary: Cation-uptake has been extensively studied in materials science. In this study, the researchers focused on a molecular crystal composed of a charge-neutral polyoxometalate (POM) capsule and discovered the occurrence of cation-coupled electron-transfer reaction. The findings reveal the significance of the POM capsule in cation uptake.
Review
Chemistry, Multidisciplinary
Luis Escobar, Qingqing Sun, Pablo Ballester
Summary: Proteins exhibit high-binding affinity and selectivity, as well as remarkable catalytic performance. The synthesis of biomimetic receptors featuring sizable aromatic cavities equipped with converging polar groups has received considerable attention. Calix[4]pyrroles and their derivatives are considered valuable receptors owing to their ability to interact with a wide variety of electron-rich, neutral, and charged guests.
ACCOUNTS OF CHEMICAL RESEARCH
(2023)
Article
Chemistry, Multidisciplinary
Gloria Tobajas-Curiel, Qingqing Sun, Jeremy K. M. Sanders, Pablo Ballester, Christopher A. Hunter
Summary: This study investigates the factors that govern aromatic interactions with heterocycles in water and in chloroform solution by analyzing supramolecular complexes formed between different calix[4]pyrrole receptors and pyridine N-oxide guests. The results highlight the complexity of the solvation processes that govern molecular recognition in water and show that non-covalent interactions between heterocyclic and aromatic rings are more favorable in water than chloroform.
