Article
Chemistry, Multidisciplinary
Chiara Di Berardino, Marcel A. Strauss, Dominic Schatz, Hermann A. Wegner
Summary: Predictive models based on incremental systems are used to estimate London dispersion interactions, successfully implemented in the azobenzene system. An equation is proposed to predict the effect of substituent changes on London dispersion interactions in azobenzenes.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Article
Chemistry, Multidisciplinary
Marcel A. Strauss, Hermann A. Wegner
Summary: The importance of London dispersion interactions in solution is a subject of ongoing debate, with the attenuation degree still not properly understood. Experimental results suggest that intramolecular dispersion is only marginally influenced, while the properties of the solvent significantly impact the half-life.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Multidisciplinary
Luka Dordevic, Lorenzo Casimiro, Nicola Demitri, Massimo Baroncini, Serena Silvi, Francesca Arcudi, Alberto Credi, Maurizio Prato
Summary: The study focused on the multi-functionalization and isomer-purity of fullerenes, presenting a light-responsive tether with azobenzene photoswitch for controlling the synthesis and distribution of bis-adducts. The results provide a new approach for controlling the covalent bis-functionalization of C60 through regulating the azobenzene photoswitch.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Applied
Xinyu Song, Jiabin Lu, Xuanying Zhu, Jiaxin Xu, Yin Jia, Meipin Liu, Lanqin Tang, Lin Sun, Ruiyu Jiang, Lei Zhang
Summary: In this study, a chromogenic molecular switch with a phenol-phthalein backbone was constructed to visually recognize acetate in pure water. The molecular switch receptor showed good selectivity and binding towards acetate, and the mechanism of acetate recognition was found to involve hydrogen bonding and proton transfer. These findings are expected to contribute to the development of a new class of aqueous anion receptors and molecular recognition mechanisms.
Article
Chemistry, Applied
Yu Liu, Linlin Zhao, Li Zhao, Bo Xu, Ce Wang, Shuangyang Li, Baocai Xu
Summary: This study reports the formation of a multi-stimuli-responsive supramolecular hydrogel through the self-assembly of an oxidized glutathione derivative. The hydrogels exhibit fibrous structures and demonstrate thermo-sensitivity, redox-responsiveness, and light-responsiveness.
Article
Chemistry, Multidisciplinary
Anna Gibalova, Luuk Kortekaas, Julian Simke, Bart Jan Ravoo
Summary: This study presents a facile and rapid approach for preparing light-responsive azo-based surface coatings through electropolymerization of carbazoles. The resulting films retain the photochemical properties and specific pH sensitivity of azo molecular switches. The electrocatalytic control over Z -> E azo double bond isomerization is facilitated by the conductive polycarbazole backbone. The highly controlled macromolecular properties of the coatings make them responsive to a range of stimuli, showing great promise for versatile application in organic electronics.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Nanoscience & Nanotechnology
Valentin Diez Cabanes, Colin Van Dyck, Silvio Osella, David Cornil, Jerome Cornil
Summary: This research introduces different concepts implemented in organic thin films and molecular junctions, as well as a new method of incorporating photochromic molecules into organic electronic devices. The discussion also highlights some issues that have been emphasized through theoretical modeling.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Chemistry, Organic
Lan-Yun Chen, Lu Wei, Yu Hai, Li-Juan Liu, Kang-Da Zhang, Tian-Guang Zhan
Summary: In this paper, a series of photoactive urea-based multiple H-bonding motifs were constructed by adding azobenzene units to the urea groups. The phototriggered isomerization of the azo units can manipulate the locking and unlocking of the urea H-bonding sites, resulting in switchable intermolecular H-bonding affinities. This development provides a generally applicable approach for the construction of urea-based H-bonded supramolecular assembly systems and materials with photoregulable properties and functions.
Article
Chemistry, Physical
Thorben Gwydion Jaik, Ulrich Jonas
Summary: This study investigates the thermally dependent absorption behavior of acrylamide derivatives using spectroscopic methods. The results show that the behavior is influenced by the formation of hydrogen bonds between molecules. This finding provides a new theoretical basis for the study of thermo-halochromism.
Article
Chemistry, Organic
Dominic Schatz, Anne Kunz, Aileen R. Raab, Hermann A. Wegner
Summary: This study reports the synthesis of nonsymmetrically substituted azobenzene derivatives and investigates the interactions between their substituents by measuring the thermal (Z)- to (E)-isomerization half-lives in n-octane. The results indicate that the London dispersion donor strength of the alkyl substrate is the decisive factor for the observed stabilization, while the electronic structure of the aryl fragment does not significantly influence the isomerization.
Article
Materials Science, Multidisciplinary
Xinhai Lv, Hongye Yan, Zhenbang Wang, Jianrong Dong, Chang Liu, Yu Zhou, Hongxiang Chen
Summary: Incorporating photochromic azobenzene groups into polymers allows for reversible photoactuation. However, damage can reduce their service scope or lifetime, making it challenging to design healable and reprocessable azobenzene-containing polymers. This study explores the impact of hydrogen bonding between urea groups on the photo-responsive behavior of polyurea elastomer and provides a feasible way to obtain healable and reprocessable azobenzene-containing polymers.
Article
Chemistry, Multidisciplinary
Simon Dubuis, Angela Dellai, Chloe Courdurie, Josianne Owona, Apostolos Kalafatis, Luc Vellutini, Emilie Genin, Vincent Rodriguez, Frederic Castet
Summary: This study combines HRS experiments and quantum chemical calculations to provide a comprehensive description of the SHG responses of DASAs. The experimental results show that derivatives incorporating a barbituric acid or an indanedione acceptor unit and N-methylaniline donor group exhibit the largest SHG responses. The calculations support the experimental data and reveal the relationship between hyperpolarizabilities, excitation energies, and charge transfer.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Inorganic & Nuclear
Idris Juma Al-Busaidi, Ashanul Haque, John Husband, Nawal K. Al Rasbi, Osama K. Abou-Zied, Rayya Al Balushi, Muhammad S. Khan, Paul R. Raithby
Summary: A series of mono-, di-, and poly(platina-ynes) incorporating stilbene spacer units were synthesized and characterized to explore the effects of ligand topology on photoisomerization and photophysical properties. The experimental findings showed that the topology-dependent reversible trans-to-cis photoisomerization occurred in certain organometallic species in CH2Cl2 solution. Computational modeling supported the experimental results.
DALTON TRANSACTIONS
(2021)
Article
Chemistry, Physical
Thamil Selvi Velayutham, M. S. Azmina, Vijayan Manickam-Achari, Alejandro Roche, Rinaa Ramesh, Alfonso Martinez-Felipe
Summary: In this study, a light-responsive organic compound was investigated for its photochromic and memory performance under electrical fields. The compound exhibited switchable conductance states and memory preservation, suggesting potential applications in resistive random-access memory (RRAM). Molecular simulations indicated that the conductivity and device performance could be enhanced and controlled by light exposure through the formation of activated Z isomers.
JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY
(2021)
Article
Pharmacology & Pharmacy
Krishna M. Gupta, Xavier Chin, Parijat Kanaujia
Summary: This study evaluated the molecular interactions between various delayed-release APIs and polymeric excipients using molecular dynamics simulations and formulated API solid dispersions using a hot melt extrusion technique. The findings suggest that NPX-Eudragit L100, NaDLO-HPMC(P), DMF-HPMC(AS), and OPZ-HPMC(AS) are the best API-polymer pairs for enhancing dissolution and oral bioavailability.
Article
Chemistry, Multidisciplinary
Daniel Kohs, Jonathan Becker, Hermann A. Wegner
Summary: In this study, a modular synthesis method was reported for the preparation of substituted cycloparaphenylenes (CPPs) of different sizes. By using a specific compound, the ring size of the final product can be conveniently controlled. Substituted nanohoops were successfully synthesized through a simple reaction and exhibited a tightly packed tube-like arrangement in the crystal structure.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Article
Biology
Viveka Nand Malviya, Ahmed Bulldan, Raffael Christoph Wende, Hassan Kabbesh, Marie-Louise Moeller, Peter Richard Schreiner, Georgios Scheiner-Bobis
Summary: This study identified a new membrane-bound androgen receptor, ZIP9, which may play a role in regulating certain physiological responses to androgens. Six tetrapeptides that could bind to the testosterone binding site of ZIP9 were synthesized and found to have pro-androgenic effects in bone cells and muscle cells. These tetrapeptides have the potential to be used as replacements for testosterone or testosterone analogs in the treatment of bone- or muscle-related disorders.
Article
Chemistry, Multidisciplinary
Artur Mardyukov, Raffael C. Wende, Peter R. Schreiner
Summary: 1,2-Ethenediols are key intermediates in prebiotic and interstellar syntheses of carbohydrates. In this study, we synthesized these enediols in the gas phase and trapped them in cryogenic argon matrices. Importantly, when subjected to photolysis at a wavelength of 180-254 nm, the enols rearrange into the simplest sugar, glycolaldehyde.
CHEMICAL COMMUNICATIONS
(2023)
Article
Chemistry, Physical
Simon Kunz, Mari Janse van Rensburg, Dennis S. Pietruschka, Andreas J. Achazi, Dominik Emmel, Felix Kerner, Doreen Mollenhauer, Hermann A. Wegner, Daniel Schroeder
Summary: Verdazyl radicals show promising potential for use in organic redox flow batteries. This study focuses on the redox behavior of these radicals, particularly in aqueous acidic electrolytes, by analyzing their species after disproportionation. The results show that participation of two electrons and two protons in the electrochemical reaction in acidic electrolytes, along with high reaction rate constants, pave the way for application in aqueous redox flow batteries pending further structural modifications.
CHEMISTRY OF MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Alexander Seitz, Raffael C. C. Wende, Peter R. R. Schreiner
Summary: We describe the site-selective acetylation of partially protected monosaccharides using immobilized oligopeptide catalysts, synthesized via solid-phase peptide synthesis. The catalysts exhibit a reversed selectivity compared to N-methylimidazole and show high selectivity for various pyranosides. The catalysts demonstrate stability for multiple reaction cycles and can be easily reused after separation from the reaction solution. They can also be used in flow without any loss of reactivity and selectivity.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Organic
Sebastian Beeck, Hermann A. Wegner
Summary: In this study, the mechanism of a novel reaction involving phthalazines, aldehydes, and thiols has been investigated. NMR spectroscopy studies and DFT computations have provided insights into the competing reaction pathway and the formation of the main by-product. These findings are significant for predicting suitable reaction substrates and further developing novel stereoselective multicomponent reactions.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Julia Ruhl, Nils Oberhof, Andreas Dreuw, Hermann A. Wegner
Summary: The incorporation of heteroatoms into hydrocarbon compounds greatly expands the chemical space of molecular materials. B-N doping has gained significant attention due to its isosterism with a C=C bond. In this study, a new and modular synthetic concept was presented to access novel diazadiborabenzo[b]triphenylenes using B-N doped biradical as intermediate. The photophysical properties revealed that the emission spectra of the diazadibora compounds can be conveniently tuned by small changes in the boron atom substitution. The new synthetic strategy provides an elegant route to various novel B-N doped acenes with great potential for applications in molecular materials.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Felix Bernt, Hermann A. Wegner
Summary: Breaking the centrosymmetry of [n]cycloparaphenylenes ([n]CPPs) by one meta connection, leads to bright emission in the typically non-fluorescent smaller derivatives, while maintaining their size-dependent emissive properties. Nitrile-substituted meta[n]CPPs (n=6, 8, 10) were prepared using the building block strategy for [n]CPPs. The nitrile substituent offers a convenient handle for functional group conversions and the photophysical properties of these novel m[n]CPP derivatives were characterized. The host-guest ability of cyano-m[10]CPP with fullerene C-60 was also explored, revealing new applications in synthetic organic chemistry, material sciences, and biomedical research.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Multidisciplinary
Jannis Volkmann, Daniel Kohrs, Hermann A. A. Wegner
Summary: In this study, the influence of different alkyl chains in malonyl ester fullerene adducts with [10]cycloparaphenylene ([10]CPP) and a tert-butyl (tBu) ester-substituted [10]CPP analogue was systematically investigated. The association constants between the nanoring hosts and the fullerene guests were determined using fluorescence quenching experiments. The trends in association were found to be a result of the interplay between repulsion caused by extended volume and London dispersion as an attractive counterpart.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Agriculture, Multidisciplinary
Fabio F. Brescia, Maximilian Koch, Raffael C. Wende, Peter R. Schreiner, Holger Zorn, Marco A. Fraatz
Summary: Among the aroma compounds formed by Cystostereum murrayi, highly potent bicyclic benzofuran derivatives are found. In addition to dill ethers, the fungus also produces two stereoisomers of a rare compound called dihydromenthofurolactones and a C3-unsaturated analogue. Analysis of reference standards allowed for the identification of the formed stereoisomers.
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
(2023)
Article
Chemistry, Physical
Yuri Tanuma, Tilen Knaflic, Bastien Anezo, Christina Stangel, Jannis Volkmann, Nikos Tagmatarchis, Hermann A. Wegner, Denis Arcon, Christopher P. Ewels
Summary: We investigated the effect of introducing C60 to (C59N)2 and [10]cycloparaphenylene ([10]CPP) using EPR measurements and DFT calculations. The incorporation of C60 resulted in the formation of stable [10]CPP D C59N-C60 center dot C [10]CPP heterodimer radicals. These radicals displayed a strong EPR signal at g = 2.0022 with a long spin coherence lifetime of 440 μs at room temperature. The [10]CPP D C59N-C60 center dot C [10]CPP oligomer was found to be more stable than C59N center dot C [10]CPP radicals and became the predominant species after thermal activation. The formation of this oligomer was thermally activated with an experimental activation energy of 0.189 eV.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Physical
Evanie Franz, Jannis Jung, Anne Kunz, Hermann A. Wegner, Olaf Brummel, Doreen Mollenhauer, Joerg Libuda
Summary: Molecular solar-thermal (MOST) systems combine solar energy conversion, storage, and release within one molecule. In this study, the catalytic activity and selectivity of three different surfaces (graphite(0001), Pt(111), and Au(111)) for energy release from the MOST system were investigated. Graphite(0001) showed the weakest reactant-surface interaction and was suitable for electrochemical triggering. Pt(111) had strong reactant-surface interactions, moderate catalytic activity, and partial decomposition, limiting its applicability. Au(111) exhibited high catalytic activity and selectivity (>99%), attributed to moderate reactant surface interaction facilitating energy release.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Torben Sassmannshausen, Anne Kunz, Nils Oberhof, Friederike Schneider, Chavdar Slavov, Andreas Dreuw, Josef Wachtveitl, Hermann A. Wegner
Summary: By synthesizing novel azobenzene-spiropyran dyads, we achieved complex photochemical control of molecular materials and nanostructures. Two different orthogonally photoswitchable systems were obtained through different connectivity patterns.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Review
Chemistry, Multidisciplinary
Daniel Kohrs, Jannis Volkmann, Hermann A. Wegner
Summary: This article highlights the application of the [2+2+2] cycloaddition method in the synthesis of substituted cycloparaphenylenes (CPPs), which offers great potential in forming substituted aromatic rings. The [2+2+2] cycloaddition can play different roles in the synthesis depending on the targeted CPP. The strategies are categorized into four classes based on the tasks fulfilled by the [2+2+2] cycloaddition, and the benefits and drawbacks of each strategy are pointed out and summarized to provide an easy insight into this research field.
CHEMICAL COMMUNICATIONS
(2022)
Article
Chemistry, Multidisciplinary
Daniel Martin-Jimenez, Michael G. Ruppert, Alexander Ihle, Sebastian Ahles, Hermann A. Wegner, Andre Schirmeisen, Daniel Ebeling
Summary: This study analyzes the suitability of qPlus sensors for modern multifrequency AFM techniques and demonstrates their ability to achieve submolecular resolution imaging. The results show that using torsional and flexural higher eigenmodes can produce good imaging results and reveal specific contrast features.