Publications associées à Hémiaminal

N-Terminal Selective C-H Azidation of Proline-Containing Peptides: a Platform for Late-Stage Diversification

Jérôme Waser, Raphaël Michel Henri Simonet-Davin, Emmanuelle Madeline Dominique Allouche

A methodology for the C-H azidation of N-terminal proline-containing peptides was developed employing only commercially available reagents. Peptides bearing a broad range of functionalities and containing up to 6 amino acids were selectively azidated at th ...

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

Rh-catalyzed C-H Bond Heteroarylation with Hypervalent Iodine Reagents and Pd-Catalyzed Tethered Functionalizations of Carbon-Carbon Multiple Bonds

Ashis Kumar Das

Transition metal-catalyzed C-H activation is a powerful tool for the synthesis of organic building blocks, materials, and natural products. Over the last decade, directing-group-assisted metal-catalyzed C-H functionalization has attracted increasing intere ...

EPFL2022

Catalytic enantioselective Pictet-Spengler reaction of carbonyl compounds: Development and application to the asymmetric total synthesis of indole alkaloids

Rémi Julien Sylvain Andres

This thesis consists in an extensive study about the enantioselective Pictet-Spengler reaction (EPSR) and its application to the total synthesis of monoterpene indole alkaloids (MIAs). The general introduction presents the literature background about this ...

EPFL2022

Controlling lignin solubility and hydrogenolysis selectivity by acetal-mediated functionalization

Jeremy Luterbacher, Anastasiia Komarova, Graham Reid Dick

Existing lignocellulosic biomass fractionation processes produce lignin with random, interunit C-C bonds that inhibit its depolymerization and constrain its use. Here, we exploit the aldehyde stabilization of lignin to tailor its structure, functionality, ...

2022

Oxidative Fluorination of Cyclopropylamides through Organic Photoredox Catalysis

Jérôme Waser, Mingming Wang

We report an oxidative ring-opening strategy to transform cyclopropylamides and cyclobutylamides into fluorinated imines. The imines can be isolated in their more stable hemiaminal form, with the fluorine atom installed selectively at the gamma or delta po ...

Wiley-VCH Verlag GmbH2020

Photocatalytic Umpolung of N- and O-substituted alkenes for the synthesis of 1,2-amino alcohols and diols

Jérôme Waser, Stefano Nicolai, Stephanie Grace Elizabeth Amos

We report an organophotocatalytic 1,2-oxyalkynylation of ene-carbamates and enol ethers using Ethynyl BenziodoXolones (EBXs). 1-Alkynyl-1,2-amino alcohols and diols were obtained in up to 89% yield. Photocatalytic formation of radical cations led to Umpolu ...

2020

Reactivity and biological activity of N,N,S-Schiff-base rhodium pentamethylcyclopentadienyl complexes

Paul Joseph Dyson, Lucinda Kate Batchelor

Neutral piano-stool complexes of the general formula [(eta(5)-C5Me5)Rh(L-OR)] (R = Me, 1; R = Et, 2; R = Pe(i), 3) have been prepared in alcohols (methanol, 1; ethanol, 2; isopropanol, 3) from the Schiff-base 5-methyl-4-{(pyridin-2-ylmethylene)amino}-4H-1, ...

ELSEVIER SCIENCE SA2020

Palladium Catalysed Intramolecular Carbo-oxygenation of Propargylic Amines to Access 1,2-Amino Alcohols and alpha-Amino Ketones via in situ Tether Formation

Phillip Gulliver Dominic Greenwood

a-Amino ketones and 1,2-amino alcohols are important structural motifs in organic chemistry, that can be observed in natural products, pharmaceutically and bioactive compounds. For these reasons, they constitute privileged targets for the development of ne ...

EPFL2020

Organocatalysts in C-N Bond Forming Reactions of Amines with CO2

Martin Hulla

The thesis describes a simple approach for N-formylation of amines with CO2 and hydrosilane reducing agents, the use of organic salts as N-formylation catalysts, their physical properties required for high catalytic activity and their role in the catalytic ...

EPFL2019

Topology of Pretreated Wood Fibers Using Dynamic Nuclear Polarization

David Lyndon Emsley, Jeremy Luterbacher, Arthur César Pinon, Pierrick Berruyer, Jasmine Viger-Gravel, Wu Lan, Michel Bardet

In the continuously developing field of lignocellulosic biomass, high-yield lignin depolymerization processes are sought to optimize its productivity and profitability. Recently, formaldehyde stabilization during lignin extraction and biomass pretreatment ...

2019

Re-assessing the Formation of N-nitrosamines during Chloramination of Various Nitrogenous Compounds using Specific and Total N-nitrosamines Analysis

Urs von Gunten, Florian Frédéric Vincent Breider, Andrea Piazzoli

N-nitrosamines (NOAs) are potent carcinogenic and mutagenic compounds that can be present in water, biological fluids, food, consumer products and cigarette smoke. Several studies have shown that the formation of NOAs in water can arise from the reactions ...

2018

Specific and total N -nitrosamines formation potentials of nitrogenous micropollutants during chloramination

Urs von Gunten, Florian Frédéric Vincent Breider, Caroline Gachet Aquillon, Andrea Piazzoli

N-nitrosamines are a group of potent human carcinogens that can be formed during oxidative treatment of drinking water and wastewater. Many tertiary and quaternary amines present in consumer products (e.g., pharmaceuticals, personal care and household prod ...

2018

In Situ Tethering Strategies for the 3-Component Synthesis of Vicinal Amino Alcohols and Diamines via Pd-Catalyzed Carboetherification and Carboamination

Ugo Jonathan Orcel

Vicinal amino alcohols and diamines are privileged motifs in organic chemistry. As such, they have been targets of choice for exploring and developing novel and more efficient strategies in organic synthesis. In this context, the difunctionalization of ole ...

EPFL2017

Dearomatization of electron poor six-membered N-heterocycles through [3+2] annulation with aminocyclopropanes

Jérôme Waser, Johannes Preindl, Shyamal Chakrabarty

Many abundant and highly bioactive natural alkaloids contain an indolizidine skeleton. A simple, high yielding method to synthesize this scaffold from N-heterocycles was developed. A wide range of pyridines, quinolines and isoquinolines reacted with donor- ...

2017

Metal-Organic Frameworks Invert Molecular Reactivity: Lewis Acidic Phosphonium Zwitterions Catalyze the Aldol-Tishchenko Reaction

Berend Smit, Daniele Ongari, Davide Tiana, Gerald Bauer, Xiangru Xu

The influence of metal-organic frameworks (MOFs) as additives is herein described for the reaction of n-alkyl aldehydes in the presence of methylvinylketone and triphenylphosphine. In the absence of a MOF, the expected Morita-Baylis-Hillman product, a beta ...

American Chemical Society2017

Kinetics and mechanisms of nitrate and ammonium formation during ozonation of dissolved organic nitrogen

Urs von Gunten, Glen Andrew De Vera

Dissolved organic nitrogen (DON) is an emerging concern in oxidative water treatment because it exerts oxidant demand and may form nitrogenous oxidation/disinfection by-products. In this study, we investigated the reactions of ozone with DON with a special ...

Elsevier2017

One-Pot Three-Component Synthesis of Vicinal Diamines via In Situ Aminal Formation and Carboamination

Jérôme Waser, Ugo Jonathan Orcel

A synthesis of vicinal diamines via in situ aminal formation and carboamination of allyl amines is reported. Employing highly electron-poor trifluoromethyl aldimines in their stable hemiaminal form was key to enable both a fast and complete aminal formatio ...

Wiley-VCH Verlag GmbH2016

Nickel-catalyzed Hydrosilylation of Alkenes and Transition-Metal-Free Intermolecular α-C-H Amination of Ethers

Ivan Buslov

Transition-metal-catalyzed hydrosilylation of olefins is one of the most important methods for the preparation of organosilicon compounds, which have broad applications in both synthetic and material chemistry. For decades, precious metals, principally pla ...

EPFL2016

Synthesis of 4-amino-1,2,3,4-tetrahydropyridine derivatives by intramolecular nucleophilic addition of tertiary enamides to in-situ generated imines

Jieping Zhu, Shuo Tong, Xu Yang

The reactivity of stable tertiary enamides in nucleophilic addition reaction with various in-situ generated imines was explored. Under very mild conditions, formyl-bearing tertiary enamides reacted with both aromatic and aliphatic amines to form imine inte ...

Elsevier2012