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Concept

Substitution électrophile aromatique

Publications associées (32)

Organocatalytic Enantioselective Pictet–Spengler Reaction of α‐Ketoesters: Development and Application to the Total Synthesis of (+)‐Alstratine A

Qian Wang, Jieping Zhu, Rémi Julien Sylvain Andres

We report herein an asymmetric Pictet– Spengler reaction of α-ketoesters. In the presence of a catalytic amount of simple alanine-derived squaramide and p-nitrobenzoic acid, reaction of tryptamines with methyl 2-oxoalkanoates afforded the corresponding 1- ...

Wiley-VCH Verlag GmbH2023

Monitoring On-Target Signaling Responses in Larval Zebrafish- Z-REX Unmasks Precise Mechanisms of Electrophilic Drugs and Metabolites

Yimon Aye, Jesse Poganik, Kuan-Ting Huang, Phillippe Ly

Reactive metabolites and related electrophilic drugs are among the most challenging small molecules to study. Conventional approaches to deconstruct the mode of action (MOA) of such molecules leverage bulk treatment of experimental specimens with an excess ...

JOURNAL OF VISUALIZED EXPERIMENTS2023

Semipinacol Rearrangement of Cyclopropenylcarbinols for the Synthesis of Highly Substituted Cyclopropanes

Jérôme Waser, Vladyslav Smyrnov

An electrophile-induced semipinacol rearrangement of cyclopropenylcarbinols is reported. This transformation gives access to various polyfunctionalized cyclopropanes under mild metal-free conditions. The scope of the reaction includes iodine, sulfur and se ...

2023

Chlorination of amides: Kinetics and mechanisms of formation of N-chloramides and their reactions with phenolic compounds

Urs von Gunten, Tianqi Zhang

Amides are common constituents in natural organic matter and synthetic chemicals. In this study, we investi-gated kinetics and mechanisms of the reactions of chlorine with seven amides, including acetamide, N-meth-ylformamide, N-methylacetamide, benzamide, ...

2023

Ni-Based Nanoparticles Catalyzed Hydrodeoxygenation of Ketones, Ethers, and Phenols to (Cyclo) Aliphatic Compounds

Paul Joseph Dyson, Yelin Hu, Mingyang Liu

Catalytic hydrodeoxygenation is of prime importance in the valorization of biomass-based feedstocks to produce essential chemicals and fuels. To carry out this process in a more cost-effective and sustainable manner, the use of 3D-metal-based nanostructure ...

Amer Chemical Soc2023

TiCl3-Mediated Reductive Cyclization of Tetrasubstituted Alkenes and Enol Esters Bearing a 2-Nitrophenyl Substituent

Dina Boyarskaya

Indole is one of the most important heterocycles widely present in bioactive natural products, pharmaceuticals, agrochemicals and materials. Being easily accessible, the 2-nitrostyrenes are attractive starting materials for the indole synthesis and the Cad ...

EPFL2023

Terminal Alkynes as One-Carbon Donors in [5+1] Heteroannulation: Synthesis of Pyridines via Ynimine Intermediates and Application in the Total Synthesis of Anibamine B

Qian Wang, Jieping Zhu, Rémi Hugo Lavernhe

Transition-metal-catalyzed [4+2] heteroannulation of alpha,beta-unsaturated oximes and their derivatives with alkynes has been developed into a powerful strategy for the synthesis of pyridines. It nevertheless lacks regioselectivity when unsymmetrically su ...

Wiley-VCH Verlag GmbH2023

The Mononuclear Metal-Binding Site of Mo-Nitrogenase Is Not Required for Activity

Wenyu Gu

The biological N-2-fixation process is catalyzed exclusively by metallocofactor-containing nitrogenases. Structural and spectroscopic studies highlighted the presence of an additional mononuclear metal-binding (MMB) site, which can coordinate Fe in additio ...

Amer Chemical Soc2023

Direct conversion of lignin to functionalized diaryl ethers via oxidative cross-coupling

Paul Joseph Dyson, Mingyang Liu

Efficient valorization of lignin, a sustainable source of functionalized aromatic products, would reduce dependence on fossil-derived feedstocks. Oxidative depolymerization is frequently applied to lignin to generate phenolic mono- mers. However, due to th ...

Nature Research2023

A Simple, Transition Metal Catalyst-Free Method for the Design of Complex Organic Building Blocks Used to Construct Porous Metal-Organic Frameworks

Wendy Lee Queen, Ilia Kochetygov, Till Marian Schertenleib, Jordi Espin Marti, Anita Justin, Jocelyn Richard Roth, Nazanin Taheri

The design of metal-organic frameworks (MOFs) having large pore sizes and volumes often requires the use of complex organic ligands, currently synthesized using costly and time-consuming palladium-catalyzed coupling chemistry. Thus, in the present work, a ...

Wiley-VCH Verlag GmbH2023

Impact of chlorination and ozonation of dissolved organic matter on its photo-induced production of long-lived photooxidants and excited triplet states

Urs von Gunten, Stephanie Christa Remke, Joanna Maria Houska

Recent studies suggested that long-lived photooxidants (LLPO), which are reactive intermediates formed during irradiation of dissolved organic matter (DOM), may consist of phenoxyl radicals derived from phenolic moieties of the DOM. Besides the well-studie ...

PERGAMON-ELSEVIER SCIENCE LTD2023

Divergent Asymmetric Total Synthesis of (−)‐Voacafricines A and B

Qian Wang, Jieping Zhu, Rémi Julien Sylvain Andres

A divergent asymmetric total synthesis of voacafricines A and B, hexacyclic monoterpene indole alkaloids, has been accomplished featuring the following key steps: a)a catalyst-controlled asymmetric Pictet– Spengler reaction of 6-methoxytryptamine with a ch ...

Wiley-VCH Verlag GmbH2023

Copper (I)‐BOX Catalyzed Asymmetric 3‐Component Reaction for the Synthesis of Trifluoromethylated Propargylic Ethers and Anilines**

Jérôme Waser, Nieves Pilar Ramirez Hernandez

An asymmetric 3-component reaction between EthynylBenziodoXoles (EBXs), 2,2,2-trifluorodiazoethane and nucleophiles catalyzed by a CuI-BOX (Bisoxazoline) catalyst is described. This protocol gives access to chiral trifluoromethylated propargyl ethers and a ...

Wiley-VCH Verlag GmbH2023

Oxidative rearrangement of 1,1-disubstituted alkenes to ketones

Qian Wang, Jieping Zhu, Qiang Feng

The Wacker process, which is widely used to convert monosubstituted alkenes into the corresponding methyl ketones, is thought to proceed through a PdII/Pd0 catalytic cycle involving a b-hydride elimination step. This mechanistic scenario is inapplicable to ...

American Association for the Advancement of Science2023

Catalytic Enantioselective Pictet–Spengler Reaction of α‐Ketoamides Catalyzed by a Single H‐Bond Donor Organocatalyst

Jieping Zhu, Qiang Wang, Rémi Julien Sylvain Andres

The asymmetric Pictet–Spengler reaction (PSR) with aldehydes is well known. However, PSR involving ketones as electrophilic partners is far-less developed. We report herein the first examples of catalytic enantioselective PSR of tryptamines with α-ketoamid ...

Wiley-VCH Verlag GmbH2022

Photochemical oxidation of phenols and anilines mediated by phenoxyl radicals in aqueous solution

Urs von Gunten, Stephanie Christa Remke

Reactive intermediates formed upon irradiation of chromophoric dissolved organic matter (CDOM) contribute to the degradation of various organic contaminants in surface waters. Besides well-studied "short-lived" photo oxidants, such as triplet state CDOM (3 ...

PERGAMON-ELSEVIER SCIENCE LTD2022

Chiral Cyclic Alkyl Amino Carbene (CAAC) Transition-Metal Complexes: Synthesis, Structural Analysis, and Evaluation in Asymmetric Catalysis

Adrien Jules Louis Madron Du Vigné

Despite recent advances in the field of cyclic alkyl amino carbenes (CAACs) including a few complementary synthetic strategies affording CAACs with various substitution patterns, the application potential of chiral CAACs to efficiently catalyze asymmetric ...

2022

Ring-Opening Reactions of Aminocyclopropanes and Aminocyclobutanes

Mingming Wang

Nitrogen-containing compounds are an important class of molecules in medicinal chemistry, chemical biology, biochemistry, material sciences or environmental sciences. Organic nitrogen occurs in many forms, ranging from small building blocks such as urea, a ...

EPFL2022

Hitting the Bullseye: Endogenous Electrophiles Show Remarkable Nuance in Signaling Regulation

Yimon Aye, Pierre Alexander Miranda Herrera

Our bodies produce a host of electrophilic species that can label specific endogenous proteins in cells. The signaling roles of these molecules are under active debate. However, in our opinion, it is becoming increasingly likely that electrophiles can rewi ...

AMER CHEMICAL SOC2022

Characterization of Chemisorbed Species and Active Adsorption Sites in Mg-Al Mixed Metal Oxides for High-Temperature CO2 Capture

Berend Smit, Kevin Maik Jablonka, Christopher Patrick Ireland

Mg-Al mixed metal oxides (MMOs), derived from the decomposition of layered double hydroxides (LDHs), have been purposed as adsorbents for CO2 capture of industrial plant emissions. To aid in the design and optimization of these materials for CO2 capture at ...

AMER CHEMICAL SOC2022