Article
Chemistry, Multidisciplinary
Marian Olaru, Stefan Mebs, Jens Beckmann
Summary: The article discusses the stabilization of phosphenium and arsenium ions through the judicious choice of aromatic substituents, resulting in molecules with specific electronic structures.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Inorganic & Nuclear
Tianqing Zhang, Vladimir Ya Lee, Shogo Morisako, Shinobu Aoyagi, Takahiro Sasamori
Summary: A bis(ferrocenyl)phosphenium ion with intramolecular phosphine-coordination, incorporated within [2]ferrocenophane framework, has been synthesized and found to be stable in air. The redox behavior of the compound, involving oxidation at the ferrocenyl moieties and reduction at the phosphorus center, has been revealed through CV measurements and theoretical calculations.
EUROPEAN JOURNAL OF INORGANIC CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Yi Luo, Bin Wang, Stef Smeets, Junliang Sun, Weimin Yang, Xiaodong Zou
Summary: Rapid phase elucidation is crucial in the development of new materials. However, routine X-ray diffraction analysis is often limited by the small size and quantity of crystalline phases. In this study, we demonstrate the use of SerialRED for high-throughput phase identification of complex polycrystalline zeolite products. By automating the analysis of hundreds of crystals, SerialRED enables the identification of zeolite phases that are undetectable using X-ray diffraction, providing new opportunities for rapid development of polycrystalline materials.
Article
Chemistry, Multidisciplinary
Daniel Roth, Alexander T. Radosevich, Lutz Greb
Summary: A series of structurally constrained phosphenium ions based on pyridinylmethylamidophenolate scaffolds are capable of undergoing P(III)/P(V) oxidative addition reactions with C-H bonds in alkynes, alkenes, and arenes. The reactions are reversible and involve isomerizations and phosphorus-ligand cooperative effects.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Marvin Janssen, Stefan Mebs, Jens Beckmann
Summary: This article compares the newly prepared and fully characterized stibenium and bismuthenium ions with previously communicated phosphenium and arsenium ions and bis(m-terphenyl) pnictogenium ions, finding that the choice of aryl substituents significantly affects molecular and electronic structures.
Article
Chemistry, Inorganic & Nuclear
Vyacheslav Sushev, Yulia Panova, Alexandra Khristolyubova, Natalia Zolotareva, Matvey Grishin, Roman Rumyantcev, Ekaterina Kozlova, Georgy Fukin, Alexander Kornev
Summary: A type of two-deck dicationic 3a,6a-diaza-1,4-diphosphapentalenes (DDP)(2)X-2 (X= halogen or complex ion) has been characterized. The interdeck distances P(1)center dot center dot center dot P(3) and P(2)center dot center dot center dot P(4) in the crystal structures exceed the sum of covalent radii but still fall within the sum of van der Waals radii. The P-31 NMR data show that phosphorus atoms are equivalent in solution, even at low temperatures (233 K). DFT calculations reveal that the formation of two equivalent P-P covalent bonds is energetically unfavorable, despite the absence of steric barriers.
EUROPEAN JOURNAL OF INORGANIC CHEMISTRY
(2023)
Article
Chemistry, Physical
Danila Gasperini, Samuel E. Neale, Mary F. Mahon, Stuart A. Macgregor, Ruth L. Webster
Summary: The utilization of phosphirenium ions as efficient pre-catalysts for metal-free carbonyl reduction with silanes is presented, alongside a detailed mechanistic study. The presence of electron-donating substituents on the phosphirenium cation favors off-cycle reactions, while electron-withdrawing substituents promote catalytic activity in hydrosilylation.
Article
Chemistry, Physical
Ugo Jacovella, Corentin Rossi, Claire Romanzin, Christian Alcaraz, Roland Thissen
Summary: The article introduces a method to retrieve structural information by using ion-molecule reactions, and uses charge transfer reactions of C6H4+ isomers as an example to illustrate the universal applicability of this method. Furthermore, it emphasizes the special reactivity characteristics of distonic ions.
Article
Chemistry, Physical
M. Vennila, R. Rathikha, S. Muthu, A. Jeelani, R. Niranjana Devi, Ahmad Irfan
Summary: This study probes various parameters and properties of the moroxydine molecule using computational methods, including geometrical properties, spectroscopy, energy gaps, molecular interactions, and drug likeness. Furthermore, molecular docking study is conducted to explore its antiviral activity.
JOURNAL OF MOLECULAR LIQUIDS
(2022)
Article
Chemistry, Physical
Rifat Jawaria, Muhammad Khalid, Jallat Khan, Muhammad Usman Khan, Ataualpa Albert Carmo Braga, Sidra Zahoor, Mohammed Mujahid Alam, Muhammad Imran
Summary: A facile condensation reaction between thiosemicarbazide and furfural successfully synthesized thiosemicarbazone derivatives with good yields, which were further characterized and analyzed using spectroscopic techniques and density functional theory. The prominent hyper-conjugative interactions between structures were found to be the main reason for stability, while the descending order of energy gaps determined the electron transfer properties.
JOURNAL OF MOLECULAR STRUCTURE
(2022)
Article
Energy & Fuels
Iryna Ivanko, Ivana Sedenkova, Andrii Mahun, Libor Kobera, Milena Hajna, Elena Tomsik
Summary: By selecting appropriate electrolytes, the working voltage of aqueous electrochemical cells can be increased, leading to a reduction in the number of cells needed. Experimental results show that utilizing ions with high solvation ability and the formation of hydronium/Zundel ions can decrease the amount of free water and minimize side reactions related to water electrolysis. Additionally, the behavior of the battery can be controlled by choosing the appropriate electrolyte.
JOURNAL OF ENERGY STORAGE
(2024)
Article
Optics
S. Iida, S. Kuma, M. Kuriyama, T. Furukawa, M. Kusunoki, H. Tanuma, K. Hansen, H. Shiromaru, T. Azuma
Summary: Research on the spontaneous and photoinduced delayed electron detachment from pentacene anions in the electrostatic ion storage ring TMU E-ring revealed the dissipation mechanisms of internal energy, radiative cooling rates, and survival probabilities. The simulation based on statistical emission processes reproduced observed behaviors and discussed the quasiexponential decrease in the temporal profile of spontaneous detachment at long times.
Article
Chemistry, Multidisciplinary
Julia M. Fehr, Nathalie Myrthil, Anna L. Garrison, Tavis W. Price, Steven A. Lopez, Ramesh Jasti
Summary: Tuning strained alkyne reactivity in organic synthesis is a growing field that focuses on cyclooctyne. Carbon nanomaterial research has produced new types of strained alkyne macrocycles, such as cycloparaphenyleneacetylenes, which have unique aromatic pi systems but are on the edge of stability. By combining synthetic accessibility and stability with curved pi systems, strained alkyne-containing cycloparaphenylenes ([n+1]CPPs) have been developed, showing size-dependent reactivity and classic characteristics of CPP. Modifications to the original design and the study of kinetics and computational models have further enhanced the properties and understanding of these carbon nanomaterials.
Article
Chemistry, Multidisciplinary
Mamta Bhandari, Mandeep Kaur, Sandeep Rawat, Sanjay Singh
Summary: In this study, the synthesis of β-diketiminate-supported aluminium complexes with terminal alkoxide and mono-thiol functional groups was reported. The electrophilic cationic species derived from these complexes showed superior Lewis acidity compared to the known methyl analogue. These complexes were also capable of activating triethylsilane in stoichiometric reactions and showed potential in hydrosilylation reactions of ethers, carbonyls, and olefins. Additionally, a new THF stabilized aluminium halide cation was reported.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Multidisciplinary
Kimberly K. Hollister, Andrew Molino, Grace Breiner, Jacob E. Walley, Kelsie E. Wentz, Ashley M. Conley, Diane A. Dickie, David J. D. Wilson, Robert J. Gilliard
Summary: This article reports the synthesis, molecular structures, and optical properties of a new class of air-stable borenium ions stabilized by the strongly donating carbodicarbene ligand. These ions exhibit thermoluminescence in solution and increased quantum yields in the solid state, with the ability to emit white light at lower temperatures. The effect of anion size and ligand rotation on the optical properties is also investigated, complemented by theoretical analysis of the excited-state dynamics.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Chemistry, Inorganic & Nuclear
Stephan Ludwig, Friederike M. Hamann, Kai Helmdach, Alexander Villinger, Wolfram W. Seidel
Summary: Eleven complexes bearing the general formula [Tp*W(CO)L{η(2)-C-2(PPh2)(2)}](n+) have been synthesized and fully characterized. The oxidation process and spectroscopic properties of the complexes are influenced by the electron character of the central metal. The basicity of the phosphine groups in the alkyne complexes is estimated. The coordination of PdCl2 affects the redox potentials and catalytic activity. X-ray diffraction analysis shows the flexibility of the alkyne complex moiety.
DALTON TRANSACTIONS
(2023)
Article
Chemistry, Multidisciplinary
Yannic Pilopp, Jonas Bresien, Daniel T. Gschwind, Alexander Villinger, Dirk Michalik, Axel Schulz
Summary: Differently substituted phenyl isonitriles and naphthyl isonitriles reacted with the cyclic biradical [P-*(mu-N-Ter)(2)P-*] (1) to form cyclic five-membered biradicals [P-*(NTer)2C(R)P-*] (2R, R= phenyl, naphthyl). C-H activation at the aryl substituent led to the formation of novel azaphospholes (5R), which were fully characterized. The addition of a second equivalent of isonitrile prevented the formation of azaphospholes by blocking the radical centers in 2R through adduct formation (3R). Quantum mechanical calculations revealed an increase in aromaticity as one of the driving forces for the activation process.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Inorganic & Nuclear
Liesa Eickhoff, Pascal Kramer, Jonas Bresien, Dirk Michalik, Alexander Villinger, Axel Schulz
Summary: In the solution, Pacman chlorophosphane (2Cl) demonstrates rapid exchange of the endo/exo-orientation of the two P-Cl bonds in the molecule, which shows cooperativity. Experimental and quantum mechanical investigations confirm the crucial role of chloride ions in this dynamic process. Homologous Pacman halogen-phosphanes 2X were prepared through halogen exchange reactions (X = F, Br, and I) to validate the results, revealing accelerated dynamic behavior for heavier analogues and significant differences in the molecular structure, including the formation of an endo-endo substituted Pacman fluorophosphane as well as dicationic species by phosphorus halogen bond dissociation.
INORGANIC CHEMISTRY
(2023)
Article
Chemistry, Inorganic & Nuclear
Lilian Sophie Szych, Karsten Paul Ludtke, Alexander Villinger, Dirk Bockfeld, Matthias Tamm, Axel Schulz
Summary: The synthesis of sterically demanding 2,6-bis-(2,4,6-trimethylphenyl)-phenyl (Ter)-stabilized and H-substituted diphosphanes via conversion of phosphide with secondary chlorophosphanes is described. The resulting potassium phosphinophosphides can be further functionalized and selectively used to synthesize Si-substituted diphosphanes or triphosphanes.
INORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Ricardo Molenda, Jonas Polkaehn, Miguel Andre Argueello Cordero, Alexander Villinger, Peter Ehlers, Stefan Lochbrunner, Peter Langer
Summary: Thieno[2 ',3 ',4 ':4,5]naphtho[1,8-cd]pyridines, S,N-doped pyrene analogs, were synthesized by combination of Pd catalyzed cross-coupling reactions and acid-mediated cycloisomerization. The modular synthesis approach allowed for the preparation of various functionalized derivatives. The photophysical properties were extensively studied using steady-state and femtosecond transient absorption along with cyclic voltammetry and (TD)-DFT calculations. The introduction of a five-membered thiophene into the 2-azapyrene scaffold resulted in redshifted emission and significant effects on excited state dynamics, such as quantum yield, lifetime, decay rates, and ISC ability, which could be further controlled by the substitution pattern of the heterocyclic scaffold.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Aleksandra Khomutetckaia, Peter Ehlers, Alexander Villinger, Peter Langer
Summary: Benzo[h]imidazo[1,2-a]quinolines and1,2a-diazadibenzo[cd,f]azulenes were synthesized via regioselectivecycloisomerization reactions starting from a common intermediate. The choice of Bronsted acid and solvent significantly influenced the selectivity of the reactions. The optical and electrochemical properties of the products were characterized using UV/vis, fluorescence, and cyclovoltammetric measurements, which were further supported by density functional theory calculations.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Edgar Zander, Jonas Bresien, Vladimir V. Zhivonitko, Johannes Fessler, Alexander Villinger, Dirk Michalik, Axel Schulz
Summary: In this study, a persistent phosphorus-centered tetraradical was isolated and found to be capable of activating small molecules. Quantum mechanical calculations were used to compare its properties and aromaticity with other known tetraradicals and biradicals.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Organic
Erich Ammon, Aleksandra Khomutetckaia, Alexander Villinger, Peter Ehlers, Peter Langer
Summary: Carba and heterocyclic benzoin derivatives were synthesized by Sonogashira coupling of alkynes with 1,2-dihaloalkenes and oxidation of the alkyne to a 1,2-diketone. Suzuki-Miyaura reaction and Pd-catalyzed nucleophilic addition to the carbonyl group were utilized for the formation of cyclic benzoin derivatives from the product of the Pd-catalyzed reaction with (2-bromophenyl)boronic acid in the presence of phenylacetylene. Previously unprecedented 5-hydroxy-5-phenylbenzo[b]naphtho[1,2-d]thiophene-6(5H)-ones and their regioisomers were prepared from 2,3-dibromobenzothiophene. Phenanthrene benzoin derivatives were synthesized from 2-bromo-1-iodobenzene.
Article
Chemistry, Organic
Arpine Vardanyan, Alexander Villinger, Peter Ehlers, Peter Langer
Summary: A new and convenient method for synthesizing aryl-substituted naphtho[2,1-a]azulenes by combining Suzuki-Miyaura, Sonogashira, and cycloisomerization reactions is reported. This methodology was used to synthesize previously unknown azuleno[1,2-h]quinolines, cyclohepta[1,2]indeno[4,5-b]thiophenes, and cyclohepta[1,2]indeno[4,5-c]thiophenes. The impact of different fused heterocyclic rings on the photophysical and electrochemical properties of these azulene derivatives was studied using experimental and theoretical methods, providing a rationale for the preparation of novel azulene derivatives with improved properties for organic material applications.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Sophie Janke, Sebastian Boldt, Pascal Nakielski, Alexander Villinger, Peter Ehlers, Peter Langer
Summary: 5-Azaullazines, indolizino[6,5,4,3-ija][1,5]naphthyridines, and their benzo-fused analogues were synthesized in three steps using Pd catalyzed cross-coupling reactions and Bronsted acid mediated cycloisomerisations. The reaction exhibited tolerance towards various substitution patterns and functional groups, resulting in high yields. The optical and electrochemical properties of selected products were experimentally studied and also characterized by DFT calculations.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Rajesh Dasi, Alexander Villinger, Malte Brasholz
Summary: 2-Cyanochromone (1) undergoes visible light-induced photocycloadditions with various alkenes using (Ir[dF(CF3)ppy](2)(dtbpy))PF6 as the photosensitizer. Mono-, di-, and trisubstituted styrenes and acrylonitriles produce [2 + 2] cycloadducts with excellent regiocontrol and high diastereoselectivity. Trialkyl-substituted alkenes yield cyclopentenone-fused chromones through a [3 + 2] cycloaddition process in moderate yields.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2023)
Article
Chemistry, Organic
Erich Ammon, Paul Heine, Miguel Andre Argueello Cordero, Stefan Lochbrunner, Alexander Villinger, Peter Langer, Peter Langer
Summary: Dibenzo[a,j] acridines and regioisomeric dibenzo[c,h]acridines were synthesized from 2,3,5,6-tetrachloropyridine using site-selective cross-coupling and alkyne-carbonyl metathesis reactions. The two regioisomeric series were obtained by changing the order of Sonogashira and Suzuki-Miyaura reactions. The optical and electronic properties of the products were studied using spectroscopy and DFT calculations.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Leon Ohms, Liesa Eickhoff, Pascal Kramer, Alexander Villinger, Jonas Bresien, Axel Schulz
Summary: We have extended the functionality of Pacman ligands by modifying them into bidentate phosphane ligands, allowing them to bind metals in a sterically protected cavity. The coordination of coinage metals demonstrates the ligand's ability to adopt various coordination modes, with some modes including the imine nitrogen atoms as well. Furthermore, the type of coordination is influenced by the substitution on the phosphorus atoms.
CHEMICAL COMMUNICATIONS
(2023)
Article
Chemistry, Inorganic & Nuclear
Priyanka Gupta, Hans-Joachim Drexler, Richard Wingad, Duncan Wass, Eszter Barath, Torsten Beweries, Christian Hering-Junghans
Summary: Phosphaalkenes are a new class of ligands similar to CO with unique electronic properties. We synthesized and characterized an iridium(I) complex with a phosphaalkene ligand, which showed versatile reactivity with different solvents or reagents. This complex exhibited good catalytic activity in the conversion of methanol and ethanol to iso-butanol, a promising biofuel candidate.
INORGANIC CHEMISTRY FRONTIERS
(2023)
Article
Chemistry, Multidisciplinary
T. Taeufer, F. Dankert, D. Michalik, J. Pospech, J. Bresien, C. Hering-Junghans
Summary: The reactivity of Cp*Ga (Cp* = C5Me5) towards phosphanylidenephosphoranes was investigated. Under irradiation at 405 nm at low temperatures, phosphagallenes (Dip)TerP = GaCp* (1a) and (Tip)TerP = GaCp* (1b) were formed, accompanied by release of PMe3. Reformation of (Ar)TerP(PMe3) and Cp*Ga was observed upon warming the reaction mixture to ambient temperatures without irradiation. 1a and 1b were isolated and found to react cleanly with CO2 and H2O to afford (Dip)TerPCO (3) and (Dip)TerPH(2) (4), respectively.