Article
Chemistry, Applied
Ramon de la Serna, Joaquin Perez-Pariente, Luis Gomez-Hortigueela
Summary: In this study, the asymmetric catalytic activity of GTM-3 chiral zeolite in the ring-opening reaction of trans-stilbene oxide using alcohols as nucleophiles was systematically explored. The results showed that a proper chiral host-guest size match is crucial for the chiral manifestation of the zeolite catalyst. Additionally, secondary alcohols with larger size exhibited higher enantioselectivity than their linear counterparts. Furthermore, variation of reaction conditions, such as the concentration of the epoxide and reaction temperature, could greatly influence the enantioselectivity and selectivity of the reaction.
Article
Chemistry, Physical
Jayashrita Debnath, Michele Parrinello
Summary: The long time scale associated with ligand residence times makes their computation challenging. The recently developed Gaussian mixture based enhanced sampling technique allows for the computation of residence times and enables an understanding of their unbinding mechanism. Guest unbinding often occurs through a series of intermediate states, which can be characterized by the number of water molecules in the binding cavity. In several cases, the residence time is correlated with water trapping times in the cavity.
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
(2022)
Article
Chemistry, Physical
Min Zhu, Martin Oestreich
Summary: A group-selective monosilylation of silanediols using List's counteranion-directed silylation methodology is described. The enantioselectivity is achieved by generating a silylium-ion-like silicon electrophile from an allylic silane paired with an imidodiphosphorimidate (IDPi), enabling discrimination of the two hydroxy groups attached to the prochiral silicon atom. Furthermore, the enantioselectivity is improved by a subsequent kinetic resolution, resulting in silicon-stereogenic disiloxanes with high enantiocontrol.
Article
Chemistry, Physical
Jian Zhang, Mingyang Song, Weijun Tang, Dong Xue, Jianliang Xiao, Huaming Sun, Chao Wang
Summary: Converting racemic compounds to enantioenriched products is a common method in accessing chiral molecules. In this study, a kinetic resolution method is used to transform racemic allylic alcohols into chiral compounds, with good yields and stereoselectivities.
Editorial Material
Chemistry, Multidisciplinary
Bing Fang, Yixuan Li, Fazheng Ren
Summary: In a recent Nature paper, Xu et al. reported the synthesis of chiral Au nanoparticles with the highest g-factor value. These chiral nanoparticles can regulate immune cell maturation, opening up the possibility of using nano scale chirality as an adjuvant for vaccines.
Article
Chemistry, Organic
Jiadong Tang, Can Chen, Tao Hong, Zibin Zhang, Chunsong Xie, Shijun Li
Summary: Supramolecular asymmetric catalysis is an important field that combines supramolecular chemistry and asymmetric catalysis. By utilizing crown ether-based host-guest chemistry and chiral phosphoric acid, the catalytic reaction can be regulated, leading to improved yield and enantioselectivity of the catalyst.
Article
Chemistry, Physical
Patricia Rodriguez-Salamanca, Gonzalo de Gonzalo, Jose A. Carmona, Joaquin Lopez-Serrano, Javier Iglesias-Siguenza, Rosario Fernandez, Jose M. Lassaletta, Valentin Hornillos
Summary: This article describes a highly enantioselective biocatalytic dynamic kinetic resolution (DKR) for configurationally labile N-arylindole aldehydes. The DKR is achieved through atroposelective bioreduction of the carbonyl group using commercial ketoreductases (KREDs), resulting in axially chiral N-arylindole aminoalcohols with excellent conversions and optical purities. The strategy relies on the racemization of the stereogenic axis facilitated by a transient Lewis pair interaction between NMe2 and the aldehyde groups. This protocol offers a broad substrate scope under mild conditions.
Article
Chemistry, Physical
Ming-Sheng Xie, Ning Li, Yin Tian, Xiao-Xia Wu, Yun Deng, Gui-Rong Qu, Hai-Ming Guo
Summary: A study reported the use of bifunctional chiral PPY N-oxides as catalysts for dynamic kinetic resolution of racemic carboxylic esters, achieving high yields and enantioselectivity for the synthesis of chiral alpha-aryl alpha-alkyl carboxylic esters. Mechanistic studies revealed the crucial role of oxygen atoms in PPY N-oxides during the reaction process.
Article
Chemistry, Multidisciplinary
Massimo Delle Piane, Luca Pesce, Matteo Cioni, Giovanni M. Pavan
Summary: Spatial confinement is widely used in nature to control chemical reactions, and supramolecular metal-organic cages have attracted increasing interest for their ability to control and accelerate reactions under confinement. However, the complex nature of these systems makes it difficult to understand the factors controlling reactivity in dynamic regimes. This study focuses on a coordination cage that can enhance the hydrolysis of amide guests by favoring their mechanical twisting under confinement. A multiscale simulation approach is used to reconstruct the reactivity in these host-guest systems, and the results are in good agreement with experimental trends. This study provides a flexible computational framework for understanding and controlling reactions in reactive host-guest systems.
Article
Chemistry, Multidisciplinary
Linlong Dai, Yuheng Liu, Qing Xu, Meifang Wang, Qiaohong Zhu, Peiyuan Yu, Guofu Zhong, Xiaofei Zeng
Summary: This paper presents a dynamic kinetic resolution method for the synthesis of axially chiral diaryl ethers. By using a Bronsted acid catalyzed atroposelective transfer hydrogenation (ATH) reaction, the desired diaryl ethers could be obtained in moderate to good chemical yields (up to 79%) and high enantioselectivities (up to 95% ee) under standard reaction conditions. These structural motifs are interesting precursors for further transformations and may have potential applications in the synthesis of chiral ligands or catalysts.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Physical
Jose A. Carmona, Carlos Rodriguez-Franco, Joaquin Lopez-Serrano, Abel Ros, Javier Iglesias-Siguenza, Rosario Fernandez, Jose M. Lassaletta, Valentin Hornillos
Summary: An efficient dynamic kinetic resolution (DKR) approach has been developed for the synthesis of axially chiral diamines based on ruthenium-catalyzed enantioselective transfer hydrogenation. This method features a broad substrate scope and proceeds under very mild conditions, allowing the preparation of BINAM homologues in good to high yields and nearly perfect enantioselectivities (up to 99% ee).
Article
Chemistry, Physical
Ming-Sheng Xie, Meng Shan, Ning Li, Yang-Guang Chen, Xiao-Bing Wang, Xuan Cheng, Yin Tian, Xiao-Xia Wu, Yun Deng, Gui-Rong Qu, Hai-Ming Guo
Summary: An efficient chiral 4-aryl-pyridine-N-oxide (ArPNO) nucleophilic organocatalyst was designed, synthesized, and successfully applied in the dynamic kinetic resolution of azoles, aldehydes, and anhydrides, providing high yields, excellent enantioselectivity, and structural diversity. Mechanistic studies revealed the key role of acyloxypyridinium cation formation and the higher nucleophilic ability of oxygen in pyridine-N-oxide, contributing to the development of diverse chiral 4-substituted pyridine-N-oxides as efficient nucleophilic organocatalysts.
Article
Chemistry, Applied
Hong-Xin Jiang, Dan-Dan Han, Rui-Ping Song, Qin Shi, Xiao-Fan He, Wan-Qing Kou, Qi Zhao, You-Dong Shao, Dao-Juan Cheng
Summary: Here, a chiral boro-phosphate catalyst is presented for an atroposelective asymmetric transfer hydrogenation method, allowing the synthesis of axially chiral styrene-type allyl alcohols. This dynamic kinetic resolution approach offers a simple procedure, mild conditions, and good enantiocontrol (51-95% ee), providing an important alternative for constructing challenging atropisomeric aryl-acyclic alkene scaffolds.
ADVANCED SYNTHESIS & CATALYSIS
(2023)
Article
Chemistry, Multidisciplinary
Yuki Saito, Shu Kobayashi
Summary: The application of heterogeneous catalysts in continuous-flow enantioselective hydroacylation reactions was studied. Catalysts were prepared by mixing supports and rhodium complexes, and showed excellent activity and enantioselectivity. Under optimized conditions, the catalysts exhibited high turnover numbers and could be applied to various substrates. Furthermore, sequential-flow reactions with other heterogeneous catalysts were demonstrated for the synthesis of biologically active molecules and functional materials.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Yan-Bo Li, Hu Tian, Shuai Zhang, Jun-Zhao Xiao, Liang Yin
Summary: In this study, a copper(I)-catalyzed reaction of diarylphosphines and O-benzoyl hydroxylamines was developed, leading to the synthesis of aminophosphinites and P-chiral aminophosphinites. The reaction mechanism was proposed and further transformation to P-chiral phosphines was achieved.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Jianyang Dong, Andreas Ostertag, Christof Sparr
Summary: In this study, the accessibility of atropisomeric o-quinodimethanes and the enantioselective synthesis of their precursors were described. The catalyst-stereocontrolled [2+2+2] cycloaddition and subsequent stereospecific Diels-Alder reactions enabled the synthesis of enantioselective compounds with high selectivity.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Xingxing Wu, Juraj Malincik, Alessandro Prescimone, Christof Sparr
Summary: The determination of absolute configuration of chiral molecular entities is crucial in stereochemistry. X-ray crystallography of quasi-racemates provides a useful approach for determining absolute configuration, especially in the development of stereoselective methods.
HELVETICA CHIMICA ACTA
(2022)
Article
Chemistry, Organic
Valentin Magne, Corentin Bellanger, Aqeel A. A. Hussein, Nathalie Saffon-Merceron, Sami Lakhdar
Summary: This article presents a metal-free synthesis method for aryltriphenylgermanes, which involves the reaction of triphenylgermane with fluoro(hetero)arenes under blue light irradiation in the presence of a base. The reaction proceeds under mild conditions and exhibits tolerance towards a few functionalities. The scope and limitations of this novel approach are analyzed based on preliminary mechanistic studies.
SYNTHESIS-STUTTGART
(2023)
Article
Multidisciplinary Sciences
Mario Gonzalez-Jimenez, Trent Barnard, Ben A. Russell, Nikita V. Tukachev, Uros Javornik, Laure-Anne Hayes, Andrew J. Farrell, Sarah Guinane, Hans M. Senn, Andrew J. Smith, Martin Wilding, Gregor Mali, Motohiro Nakano, Yuji Miyazaki, Paul McMillan, Gabriele C. Sosso, Klaas Wynne
Summary: It has been discovered that the boson peak in glasses, which is an excess in heat capacity or an additional peak in the terahertz vibrational spectrum, can be isolated in liquids of highly symmetric molecules using depolarized Raman scattering. This peak is linked to the formation of clusters consisting of about 20 molecules. These findings represent a significant step toward understanding the physics of vitrification.
NATURE COMMUNICATIONS
(2023)
Article
Chemistry, Multidisciplinary
Tanno A. Schmidt, Stephan Schumann, Andreas Ostertag, Christof Sparr
Summary: In this study, we report the stereoselective synthesis of triptycyl sulfones with atropisomerism using a chiral phosphoric acid catalyst. The oxidation of a stereodynamic thioether controlled by the catalyst allowed selective access to enantioenriched triptycyl sulfoxides. Subsequent enantiospecific and diastereoselective catalytic oxidation resulted in overall control over the stereogenic C-S axis, with a stereoselectivity of up to (-sc): (+sc) : (ap)=94 : 6 :<1.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Correction
Multidisciplinary Sciences
Mario Gonzalez-Jimenez, Trent Barnard, Ben A. Russell, Nikita V. Tukachev, Uros Javornik, Laure-Anne Hayes, Andrew J. Farrell, Sarah Guinane, Hans M. Senn, Andrew J. Smith, Martin Wilding, Gregor Mali, Motohiro Nakano, Yuji Miyazaki, Paul McMillan, Gabriele C. Sosso, Klaas Wynne
NATURE COMMUNICATIONS
(2023)
Article
Chemistry, Multidisciplinary
Valentin Quint, Thi Hong Van Nguyen, Gary Mathieu, Saloua Chelli, Martin Breugst, Jean-Francois Lohier, Annie-Claude Gaumont, Sami Lakhdar
Summary: Regioselective phosphonation of pyridines can be achieved through activation of the pyridine ring with a Lewis acid to enable nucleophilic addition of a phosphine oxide anion, followed by oxidation with an organic oxidant. This method provides access to various 4-phosphonated pyridines with good to excellent yields. In addition, C2-phosphonated pyridines can be synthesized using strong Lewis basic phosphorus nucleophiles or strong Lewis acidic pyridines in certain cases. The mechanistic investigations help understand the factors controlling the reactivity and selectivity of this reaction.
ACS ORGANIC & INORGANIC AU
(2023)
Article
Chemistry, Multidisciplinary
Daniel Moser, Kalipada Jana, Christof Sparr
Summary: In this study, the feasibility of atroposelective P-III/P-V=O redox organocatalysis by the Staudinger-aza-Wittig reaction is described. The formation of isoquinoline heterocycles allows for the synthesis of a wide range of valuable atropisomers with high enantioselectivities. The reaction is catalyzed by a chiral phosphine catalyst, with stereocontrol achieved through a silane reductant and Bronsted acid co-catalysis. The products can be easily transformed into N-oxides, naphthol, and triaryl phosphine variants, providing access to diverse aromatic heterocycles with precise control over their configuration.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Physical
Tobias Vornholt, Zlatko Joncev, Valerio Sabatino, Sven Panke, Thomas R. Ward, Christof Sparr, Markus Jeschek
Summary: This study presents a biocatalytic strategy using artificial metalloenzymes for achieving atroposelective synthesis of binaphthalene compounds through ring-closing metathesis in aqueous media. It demonstrates that atroposelectivity can be fine-tuned by engineering amino acid residues within the streptavidin host protein. The resulting artificial metalloenzymes promote product formation with high enantiomeric ratios, and this approach offers an attractive and sustainable synthesis route for drug molecules and other compounds of interest.
Article
Chemistry, Organic
Valeriia Hutskalova, Farhan Bou Hamdan, Christof Sparr
Summary: An efficient methodology for the photoredox- and nickel-catalyzed aminocarbonylation of (hetero)aryl bromides was developed using readily available oxamic acids and a widely used organic photoredox catalyst. This transformation provides an attractive alternative to classical amidation procedures, with mild reaction conditions.
Article
Chemistry, Multidisciplinary
Daniel Moser, Tanno A. Schmidt, Christof Sparr
Summary: This Perspective discusses the benefits and challenges of catalyst-controlled diastereodivergence in constructing carbon stereocenters, and extends these concepts to diastereodivergent catalysis for atropisomeric systems and E- and Z-configured alkenes.
Article
Chemistry, Organic
Hend Besrour, Matthieu Hedouin, Lina Truong, Sami Lakhdar, Hassan Oulyadi
Summary: In this study, the interaction between a diphenyliodonium salt and trivalent phosphorus compounds was investigated using {H-1, F-19, P-31} NMR and DFT calculations. The importance of blue light in the reaction was highlighted, and the formation of a phosphonium intermediate was identified. The formation of an EDA complex was characterized, and the significance of acetonitrile for the formation of this complex was demonstrated. The study was further extended to other phosphonium salt formation reactions, and the stability and photoreactivity of the complexes were investigated using DFT calculations.
ORGANIC CHEMISTRY FRONTIERS
(2023)
Article
Chemistry, Multidisciplinary
Ben A. Russell, Mario Gonzalez-Jimenez, Nikita V. Tukachev, Laure-Anne Hayes, Tajrian Chowdhury, Uros Javornik, Gregor Mali, Manlio Tassieri, Joy H. Farnaby, Hans M. Senn, Klaas Wynne
Summary: This study discovered a single-component homogeneous molecular liquid that exhibits two comparable glass transitions, one associated with dynamic arrest of liquid properties and the other associated with the freezing out of intramolecular degrees of freedom.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Bjorn Pfund, Valeriia Hutskalova, Christof Sparr, Oliver S. Wenger
Summary: By modifying acridinium dyes, a new family of organic photocatalysts called isoacridones was obtained, which have both photoactive singlet- and triplet-excited states. These isoacridone dyes have high intersystem crossing efficiencies and can store significant amounts of energy. They can be used for parallel triplet-triplet energy transfer and photoinduced electron transfer, making them suitable for modern photocatalysis. In proof-of-principle experiments, the isoacridone dyes demonstrated their potential for applications such as arene reductions and C-C couplings. Additionally, by combining with an annihilator, sensitized triplet-triplet annihilation upconversion was achieved.
Article
Chemistry, Multidisciplinary
Saif Eddine Cherif, Avisek Ghosh, Saloua Chelli, Isabelle M. Dixon, Jamil Kraiem, Sami Lakhdar
Summary: This work demonstrates a novel approach to obtain the thermodynamically unfavorable Z-isomer in olefin cross-metathesis reactions by combining a classical E-selective catalyst with a readily available photocatalyst. The scope and limitations of this approach are discussed based on computational and experimental mechanistic data.
