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Concept

Racémique

Publications associées (26)

Chalcogen bonding catalysis

Jieping Zhu

Catalysts play a major role in chemical synthesis, and catalysis is considered to be a green and economic process. Catalysis is dominated by covalent interactions between the catalyst and substrate. The design of non-covalent catalysts came into limelight ...

Royal Society of Chemistry2024

Catalytic Enantioselective Synthesis of Inherently Chiral Macrocycles by Dynamic Kinetic Resolution

Jieping Zhu, Shuo Tong

Kinetically fast racemization of chiral substrates through an achiral intermediate and enantioselective functionalization of one of the enantiomeric substrates forms the basis of the dynamic kinetic resolution (DKR) of centrally chiral molecules. We report ...

2024

Micropreparative Gel Electrophoresis for Purification of Nanoscale Bioconjugates

Ardemis Anoush Boghossian, Yahya Rabbani, Shang-Jung Wu, Vitalijs Zubkovs, Sayyed Hashem Sajjadi

Conventional techniques for purifying macromolecular conjugates often require complex and costly installments that are inaccessible to most laboratories. In this work, we develop a one-step micropreparative method based on a trilayered polyacrylamide gel e ...

2024

Chiral magnetohydrodynamics with zero total chirality

Salim Bennouna

We study the evolution of magnetic fields coupled with chiral fermion asymmetry in the framework of chiral magnetohydrodynamics with zero initial total chirality. The initial magnetic field has a turbulent spectrum peaking at a certain characteristic scale ...

American Physical Society2023

Enantio- and diastereoselective construction of vicinal C(sp(3)) centres via nickel-catalysed hydroalkylation of alkenes

Xile Hu, Srikrishna Bera, Chao Fan

In drug discovery, the proportion of aliphatic carbons (C(sp(3))) and the presence of chiral carbons in organic molecules are positively correlated to their chance of clinical success. Although methods exist for the synthesis of chiral C(sp(3))-rich molecu ...

2022

In depth analysis of heterogeneous catalysts for the chemoenzymatic dynamic kinetic resolution of beta-amino esters

Kumar Varoon Agrawal, Cédric Karel J Van Goethem

The chemoenzymatic dynamic kinetic resolution of beta-amino esters is established after detailed evaluation of metal-based heterogeneous catalysts for racemization and enzyme catalysts for kinetic resolution. Several heterogeneous palladium catalysts prove ...

ROYAL SOC CHEMISTRY2022

Hard X-ray helical dichroism of disordered molecular media

Majed Chergui, Giulia Fulvia Mancini, Malte Oppermann, Oliviero Cannelli, Dominik Kinschel, Camila Bacellar Cases Da Silveira

Chirality is a structural property of molecules lacking mirror symmetry that has strong implications in diverse fields, ranging from life sciences to materials science. Chirality-sensitive spectroscopic methods, such as circular dichroism, exhibit weak sig ...

Nature Publishing Group2022

Schiff base ligands derived from 1,2-bis(2 '-nitro-/amino-phenoxy)-3-R-benzene and 2-hydroxy-1-naphthaldehyde and their Cu/Zn(II) complexes: synthesis, characterization, X-ray structures and computational studies

Rosario Scopelliti

1,2-Bis(2'-nitrophenoxy)-3-R-benzenes {R = H (1), CH3 (2) and OCH3 (3)} have been prepared from the S-N-Ar reaction between 1-fluoro-2-nitrobenzene and 3-R-catechol (aromatic diol), and are then reduced to the corresponding diamines 1,2-bis(2'-aminophenoxy ...

ROYAL SOC CHEMISTRY2021

Visible-Light-Driven Catalytic Deracemization of Secondary Alcohols

Xile Hu, Zhikun Zhang

Deracemization of racemic chiral compounds is an attractive approach in asymmetric synthesis, but its development has been hindered by energetic and kinetic challenges. Here we describe a catalytic deracemization method for secondary benzylic alcohols whic ...

Wiley-VCH Verlag GmbH2021

Chiral Cyclopentadienyl Ligands: Design, Syntheses, and Applications in Asymmetric Catalysis

Nicolai Cramer, Benoît Daniel Bertrand Audic, Josep Más-Roselló, Aragorn Nathan Laverny, Ana Garcia Herraiz

The creation of new chiral ligands capable of providing high stereocontrol in metal-catalyzed reactions is crucial in modern organic synthesis. The production of bioactive molecules as single enantiomers is increasingly required, and asymmetric catalysis w ...

Wiley-VCH Verlag GmbH2021

Catalytic Enantioselective Transformations with Chiral Cyclopentadienyl Ruthenium(II) Complexes

Sung Hwan Park

The chemistry of cyclopentadienyl ruthenium(II) complexes plays an important role in ruthenium catalysis because of its high potential for various transformations. However, asymmetric catalysis with chiral cyclopentadienyl ruthenium(II) complexes is still ...

EPFL2020

Iridium-catalyzed acid-assisted asymmetric hydrogenation of oximes to hydroxylamines

Nicolai Cramer, Josep Más-Roselló

Asymmetric hydrogenations are among the most practical methods for the synthesis of chiral building blocks at industrial scale. The selective reduction of an oxime to the corresponding chiral hydroxylamine derivative remains a challenging variant because o ...

American Association for the Advancement of Science2020

Interplay of H-Bonds with Aromatics in Isolated Complexes Identifies Isomeric Carbohydrates

Oleg Boyarkine, Vladimir Kopysov, Aleksandr Pereverzev, Ruslan Yamaletdinov

The tremendous isomeric diversity of carbohydrates enables a wide range of their biological functions but makes the identification and study of these molecules difficult. We investigated the ability of intermolecular interactions to communicate structural ...

Wiley-VCH Verlag GmbH2019

Accessible Superchiral Near-Fields Driven by Tailored Electric and Magnetic Resonances in All-Dielectric Nanostructures

Hatice Altug, Andreas Tittl, Yasaman Jahani, Kosmas Tsakmakidis, Ershad Mohammadi

Detection and differentiation of enantiomers in small quantities are crucially important in many scientific fields, including biology, chemistry, and pharmacy. Chiral molecules manifest their handedness in their interaction with the chiral state of light ( ...

AMER CHEMICAL SOC2019

Single-step conversion of lignin monomers to phenol: Bridging the gap between lignin and high-value chemicals

Paul Joseph Dyson, Ning Yan

Transformation of lignin into high-value chemicals is hampered by the complexity of monomers obtained from lignin depolymerization. Here we report a strategy, composed of hydro-demethoxylation and de-alkylation reactions, that is able to chemically converg ...

2018

Chiral expression of adsorbed (MP) 5-amino[6] helicenes: from random structures to dense racemic crystals by surface alloying

Magalí Alejandra Lingenfelder

The chiral expression of a molecule on a surface is driven from a random solid solution on Cu(100) to a racemic crystal on a Sn/Cu(100) alloy. Density functional theory simulations reveal how the growth of the racemate is influenced by the underlying surfa ...

Royal Society of Chemistry2017

Deactivation Aspects of Methane Oxidation Catalysts Based on Palladium and ZSM-5

Davide Ferri

Catalytic methane oxidation is used in exhaust gas after treatment to reduce methane emissions in stationary combustion processes as well as in natural gas vehicles. Pd/zeolite catalysts provide higher activity than the commonly used Pd/Al2O3, but suffer f ...

Springer Verlag2017

Synthesis, Properties, and Two-Dimensional Adsorption Characteristics of 5-Amino[6]hexahelicene

Magalí Alejandra Lingenfelder

A convergent synthesis of racemic 5-amino[6]hexahelicene is described. Cross-coupling reactions are used to assemble a pentacyclic framework, and a metal-catalyzed ring-closure comprises the final step. The enantiomers were separated by means of chromatogr ...

Wiley-Blackwell2016

Racemization of undesired enantiomers: Immobilization of mandelate racemase and application in a fixed bed reactor

Production of optically pure products can be based on simple unselective synthesis of racemic mixtures combined with a subsequent separation of the enantiomers; however, this approach suffers from a 50% yield limitation which can be overcome by racemizatio ...

Wiley-V C H Verlag Gmbh2016

Stereocontrolled Self-Assembly and Self-Sorting of Luminescent Europium Tetrahedral Cages

Jean-Claude Bünzli

Coordination-directed self-assembly has become a well-established technique for the construction of functional supramolecular structures. In contrast to the most often exploited transition metals, trivalent lanthanides Ln(III) have been less utilized in th ...

American Chemical Society2015