Publications related to Halogenation

Tandem catalysis enables chlorine-containing waste as chlorination reagents

Paul Joseph Dyson, Mingyang Liu, Xinbang Wu

Chlorinated compounds are ubiquitous. However, accumulation of chlorine-containing waste has a negative impact on human health and the environment due to the inapplicability of common disposal methods, such as landfill and incineration. Here we report a su ...

Nature Portfolio2024

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

Chemo- and regio-divergent access to fluorinated 1-alkyl and 1-acyl triazenes from alkynyl triazenes

Kay Severin, Nicolai Cramer, Carl Thomas Bormann, Jin Fay Tan

The 1,1,2,2-tetrafluoroethylene unit is prevalent in bioactive molecules and functional materials. Despite being in principle a straightforward strategy to access this motif, the direct tetrafluorination of alkynes involves very hazardous or inconvenient r ...

2022

Chlorination of arenes via the degradation of toxic chlorophenols

Paul Joseph Dyson, Mingyang Liu, Xuemei Yang

Aryl chlorides are among the most versatile synthetic precursors, and yet inexpensive and benign chlorination techniques to produce them are underdeveloped. We propose a process to generate aryl chlorides by chloro-group transfer from chlorophenol pollutan ...

2022

Engaging 1-Alkynyl Triazenes in Transition Metal-Catalyzed and Fluorinative Transformations

Jin Fay Tan

Triazenes have garnered great attention for their anti-cancer properties and versatility in organic chemistry. Recently, a novel synthesis of 1-alkynyl triazenes was reported. This thesis describes the compatibility, reactivity and applications of 1-alkyny ...

EPFL2021

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

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

Versatile Route to trans-Platinum(II) Complexes via Manipulation of a Coordinated 3-(Pyridin-3-yl)propanoicAcid Ligand

Paul Joseph Dyson, Tina Riedel, Marta Maroto Diaz

We describe the direct coupling of alcohols and amines to a 3-(pyridin-3-yl)propanoic acid ligand coordinated to a Pt(II) to afford ester and amide derivatives. Using this approach, a family of trans-Pt(II) compounds with amine ligands bearing long perfluo ...

2019

Formation of brominated trihalomethanes during chlorination or ozonation of natural organic matter extracts and model compounds in saline water

Urs von Gunten

Oxidation experiments (chlorine, ozone and bromine) were carried out with synthetic saline waters containing natural organic matter (NOM) extracts and model compounds to evaluate the potential of these surrogates to mimic the formation of brominated trihal ...

2018

Room temperature C(sp(2))-H oxidative chlorination via photoredox catalysis

Xile Hu, Lei Zhang

Photoredox catalysis has been developed to achieve oxidative C-H chlorination of aromatic compounds using NaCl as the chlorine source and Na2S2O8 as the oxidant. The reactions occur at room temperature and exhibit exclusive selectivity for C(sp(2))-H bonds ...

Royal Soc Chemistry2017

The Role of Bromide in Oxidative Water Treatment

Michèle Bernadette Heeb

Bromide (Br-) levels in fresh waters range from a few ¿gL-1 to several mgL-1. In seawater its concentration is about 67 mgL-1. The goal of this thesis is to assess the fate of bromide during oxidative water treatment and to explore its influence on these t ...

EPFL2016

A Highly Chemoselective and Practical Alkynylation of Thiols

Jérôme Waser, Reto Frei

A thiol-alkynylation procedure utilizing the hypervalent iodine alkyne transfer reagent TIPS-ethynyl-benziodoxolone has been developed. This scalable reaction proceeds in five minutes at room temperature in an open flask using commercially available reagen ...

American Chemical Society2013

Ozonation of iodide-containing waters: Selective oxidation of iodide to iodate with simultaneous minimization of bromate and I-THMs

Urs von Gunten

The presence of iodinated disinfection by-products (I-DBPs) in drinking water poses a potential health concern since it has been shown that I-DBPs are generally more genotoxic and cytotoxic than their chlorinated and brominated analogs. I-DBPs are formed d ...

Elsevier2013

Biological reduction of chlorinated solvents: Batch-scale geochemical modeling

David Andrew Barry, Clare Robinson

Simulation of biodegradation of chlorinated solvents in dense non-aqueous phase liquid (DNAPL) source zones requires a model that accounts for the complexity of processes involved and that is consistent with available laboratory studies. This paper describ ...

Elsevier2010

Diversity-oriented synthesis of furo[3,2-f]chromanes with antimycobacterial activity

Stewart Cole

We previously reported the synthesis and the antimycobacterial activity of 4-(7,7-dimethyl-7H-furo[3,2-f]chromen-2-yl)pyridine. From this result, we sought to design simple synthetic accesses to related structures allowing the preparation of a diverse set ...

2009

pH control for enhanced reductive bioremediation of chlorinated solvent source zones

David Andrew Barry, Clare Robinson

Enhanced reductive dehalogenation is an attractive treatment technology for in situ remediation of chlorinated solvent DNAPL source areas. Reductive dehalogenation is an acid-forming process with hydrochloric acid and also organic acids from fermentation o ...

Elsevier2009

Atom-Transfer Radical Addition Reactions Catalyzed by RuCp* Complexes: A Mechanistic Study

Kay Severin, Andrzej Sienkiewicz, Gregor Kiefer, Katrin Anne Thommes, Katarzyna Pierzchala

Kinetic and spectroscopic analyses were performed to gain information about the mechanism of atom-transfer radical reactions catalyzed by the complexes [RuCl2Cp*(PPh3)] and [RuClCp*(PPh3)2] (Cp*=pentamethylcyclopentadienyl), in the presence and in the abse ...

2009

In search of simplicity and flexibility: a rational access to twelve fluoroindolecarboxylic acids

Assunta Ginanneschi

All twelve indolecarboxylic acids carrying both a fluorine substituent and a carboxy group at the benzo ring have been prepd. either directly from the corresponding fluoroindoles or from the chlorinated derivs. by hydrogen/metal permutation ("metalation"), ...

2006

Fluorinated β-Diketones for the Extraction of Lanthanide Ions: Photophysical Properties and Hydration Numbers of Their EuIII Complexes

Jean-Claude Bünzli, Anne-Sophie Chauvin, Frédéric Gumy

Tris(β-diketonato)europium(III) with a series of variably fluorinated ligands derived from 3,5-heptanedione were synthesised with the aim of determining their hydration state under extraction conditions. The number of coordinated water molecules was determ ...

2006

Fluorine in an heteroaromatic context : functionalization of halopyridines

Thierry Rausis

The organometallic approach to the functionalization of arenes and heteroarenes has recently been investigated by our group introducing modifications of the standard methods. This includes, in particular, the basicity-driven heavy halogen migration, which ...

EPFL2005