Publications related to Organobromine chemistry

Modelling the coupled mercury-halogen-ozone cycle in the central Arctic during spring

Julia Schmale, Ivo Fabio Beck, Hélène Paule Angot, Jenny Thomas

Near-surface mercury and ozone depletion events occur in the lowest part of the atmosphere during Arctic spring. Mercury depletion is the first step in a process that transforms long-lived elemental mercury to more reactive forms within the Arctic that are ...

2023

Diverting the 5-exo-Trig Oxypalladation to Formally 6-endo-Trig Fluorocycloetherification Product through 1,2-O/Pd(IV) Dyotropic Rearrangement

Qian Wang, Jieping Zhu, Jing Gong

Pd-catalyzed cyclizative functionalization of γ-hydroxyalkenes affords tetrahydrofuran derivatives via a key 5-exo-trig oxypalladation step. Herein, we report a palladium(II)-catalyzed, Selectfluor-mediated formal 6-endo-trig fluorocycloetherification of γ ...

2023

Reactivity of Bromine Radical with Dissolved Organic Matter Moieties and Monochloramine: Effect on Bromate Formation during Ozonation

Urs von Gunten, Sung Eun Lim

Bromine radical (Br center dot) has been hypothesized to be a key intermediate of bromate formation during ozonation. Once formed, Br center dot further reacts with ozone to eventually form bromate. However, this reaction competes with the reaction of Br c ...

AMER CHEMICAL SOC2023

Migrative Carbofluorination of Saturated Amides Enabled by Pd-Based Dyotropic Rearrangement

Qian Wang, Jieping Zhu, Anne-Clémence Corminboeuf, Hua Wu, Simone Gallarati, Guoqiang Yang

Directly editing an all-carbon quaternary carbon itself of nonstrained acyclic molecules remains underexploited despite the recent advances in the fields of both C–H and C–C bond activation. Herein, we report a palladium-catalyzed migrative carbofluorinati ...

ACS2022

Reaction of DMS and HOBr as a Sink for Marine DMS and an Inhibitor of Bromoform Formation

Urs von Gunten, Boris Droz

Recently, we suggested that hypobromous acid (HOBr) is a sink for the marine volatile organic sulfur compound dimethyl sulfide (DMS). However, HOBr is also known to react with reactive moieties of dissolved organic matter (DOM) such as phenolic compounds t ...

2021

Z-Selective Synthesis of Vinyl Boronates through Fe-Catalyzed Alkyl Radical Addition

Xile Hu, Alexis Baptiste Cheseaux, Guido Barzanò

Z-Selective synthesis of vinyl boronates is challenging. This work describes Fe-catalyzed addition of alkyl radicals, formed by the corresponding alkyl halides, to ethynyl ethynylboronic acid pinacol ester that gives rise to Z-vinyl boronates in high stere ...

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

Molecular mechanism of NDMA formation from N,N-dimethylsulfamide during ozonation: Quantum chemical insights into a bromide-catalyzed pathway

Urs von Gunten, Jeremy Samuel Arey, Daniela Trogolo, Michèle Bernadette Heeb, Brijesh Kumar Mishra

During ozonation of drinking water, the fungicide metabolite NN-dimethyIsulfamide (DMS) can be transformed into a highly toxic product, N-nitrosodimethylamine (NDMA). We used quantum chemical computations and stopped-flow experiments to evaluate a chemical ...

Amer Chemical Soc2015

Mechanistic Study on the Formation of Cl-/Br-/I-Trihalomethanes during Chlorination/Chloramination Combined with a Theoretical Cytotoxicity Evaluation

Urs von Gunten

Chlorination followed by chloramination can be used to mitigate the formation of potentially toxic iodinated disinfection byproducts (I-DBPs) while controlling the formation of regulated chloro-bromo-DBPs (Cl-/Br-DBPs). Water samples containing dissolved o ...

American Chemical Society2015

Formation of disinfection by-products during ballast water treatment with ozone, chlorine, and peracetic acid: influence of water quality parameters

Urs von Gunten

As ocean-going ships begin implementing chemical disinfection to treat ballast water, the potential formation of disinfection by-products (DBPs) is an important issue of concern. This is especially critical since ballast waters are often saline, and the in ...

Royal Soc Chemistry2015

Oxidative treatment of bromide-containing waters: Formation of bromine and its reactions with inorganic and organic compounds - A critical review

Urs von Gunten, Michèle Bernadette Heeb, Saskia Gisela Zimmermann-Steffens

Bromide (Br-) is present in all water sources at concentrations ranging from similar to 10 to >1000 mu g L-1 in fresh waters and about 67 mg L-1 in seawater. During oxidative water treatment bromide is oxidized to hypobromous acid/hypobromite (HOBr/OBr-) a ...

Elsevier2014

Reactivity of BrCl, Br2, BrOCl, Br2O and HOBr toward dimethenamid in solutions of bromide + aqueous free chlorine

Jeremy Samuel Arey, Peter Rudolf Tentscher

HOBr, formed via oxidation of bromide by free available chlorine (FAC), is frequently assumed to be the sole species responsible for generating brominated disinfection byproducts (DBPs). Our studies reveal that BrCl, Br-2, BrOCl, and Br2O can also serve as ...

Amer Chemical Soc2013

Iodate and Iodo-Trihalomethane Formation during Chlorination of Iodide-Containing Waters: Role of Bromide

Urs von Gunten

The kinetics of iodate formation is a critical factor in mitigation of the formation of potentially toxic and off flavor causing iodoorganic compounds during chlorination. This study demonstrates that the formation of bromine through the oxidation of bromi ...

2012

Cinétique de réaction hétérogène d'importance troposphérique sur des substrats modèles et sur des aérosols

Pascal Pratte

The first part of this study consists in the investigation of the evaporation and the condensation rate of H2O in the presence of different types of ice in a low pressure flow reactor. The second part of the present work reports the study of chlorine activ ...

EPFL2006