Publications related to Synthetic colorant

Isolation, Characterisation and Reactivity of N-Heterocyclic Diazoolefins

Examples for applications of nitrous oxide in organic synthesis remain rare up until today. First mayor contributions of our group were published in 2012, when nitrous oxide was successfully captured by N-heterocyclic carbenes. Subsequent studies investiga ...

EPFL2022

Learning the Exciton Properties of Azo-dyes

Anne-Clémence Corminboeuf, Ksenia Briling, Alberto Fabrizio, Sergio Vela Llausi

The ab initio determination of electronic excited state (ES) properties is the cornerstone of theoretical photochemistry. Yet, traditional ES methods become impractical when applied to fairly large molecules, or when used on thousands of systems. Machine l ...

AMER CHEMICAL SOC2021

Photocatalysis with organic dyes: facile access to reactive intermediates for synthesis

Jérôme Waser, Marion Marie-Agnès Garreau, Stephanie Grace Elizabeth Amos, Luca Buzzetti

Organic dyes have emerged as a reliable class of photoredox catalysts. Their great structural variety combined with the easy finetuning of their electronic properties has unlocked new possibilities for the generation of reactive intermediates. In this revi ...

2020

The Photoisomerization Pathway(s) of Push‐Pull Phenylazoheteroarenes

Anne-Clémence Corminboeuf, Sergio Vela Llausi

Azoheteroarenes are the most recent derivatives targeted to further improve the properties of azo‐based photoswitches. Their light‐induced mechanism for trans‐cis isomerization is assumed to be very similar to that of the parent azobenzene. As such, they i ...

2020

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

Dyes, Radicals and Nitrous Oxide Adducts Derived from N-Heterocyclic Carbenes

Léonard Yannick Maurice Eymann

N-Heterocyclic carbenes are able to form covalent adducts with nitrous oxide (N2O) under ambient conditions. This thesis summarizes the studies of these adducts and their reactivity. A ditopic carbanionic N-heterocyclic carbene was found to react with nit ...

EPFL2018

Lanthanide light for biology and medical diagnosis

Jean-Claude Bünzli

Optical imaging emerges as a vital component of the various techniques needed to meet the stringent requirements of modern bioanalysis and bioimaging. Lanthanide luminescent bioprobes (LLBs) have greatly contributed to this field during the past 35 years b ...

Elsevier Science Bv2016

Novel Blue Organic Dye for Dye-Sensitized Solar Cells Achieving High Efficiency in Cobalt-Based Electrolytes and by Co-Sensitization

Michael Graetzel, Shaik Mohammed Zakeeruddin, Ulf Anders Hagfeldt, Jiahuan Zhang, Kazuteru Nonomura, Yan Hao, Yasemin Saygili, Anna Eriksson, Enrico Polanski

Blue and green dyes as well as NIR-absorbing dyes have attracted great interest because of their excellent ability of absorbing the incident photons in the red and near-infrared range region. A novel blue D-pi-A dye (Dyenamo Blue), based on the diketopyrro ...

2016

Synthetic chemistry with nitrous oxide

Kay Severin

This review article summarizes efforts to use nitrous oxide (N2O, ‘laughing gas’) as a reagent in synthetic chemistry. The focus will be on reactions which are carried out in homogeneous solution under (relatively) mild conditions. First, the utilization o ...

Royal Society of Chemistry2015

Effect of pi-spacers on the photovoltaic properties of D-pi-A based organic dyes

Mohammad Khaja Nazeeruddin, Paramaguru Ganesan

Three new triphenylamine based D-pi-pi-A (TPC, TSC and TOC) dyes with different pi-spacers have been synthesized and analysed their significance on the photophysical properties and photovoltaic applications. The synthesized dyes were characterized by NMR, ...

Elsevier Science Sa2015

Influence of Dye Architecture of Triphenylamine Based Organic Dyes on the Kinetics in Dye-Sensitized Solar Cells

Ulf Anders Hagfeldt, Gunther Wittstock

The impact of the dye architecture on the kinetics in the dyesensitized solar cell (DSC) was investigated for two structurally similar organic dyes, adsorbed adsorbed to a mesoporous TiO2 film. Differences in the HOMO and LUMO levels of the triphenylamine ...

American Chemical Society2015

Molecular Engineering of Pyrido[3,4-b]pyrazine-Based Donor-Acceptor-pi- Acceptor Organic Sensitizers: Effect of Auxiliary Acceptor in Cobalt- and Iodine-Based Electrolytes

Michael Graetzel, Shaik Mohammed Zakeeruddin, Jean-David Décoppet, Fabrizio Giordano, Bo Liu

Due to the ease of tuning its redox potential, the cobalt-based redox couple has been extensively applied for highly efficient dye-sensitized solar cells (DSSCs) with extraordinarily high photovoltages. However, a cobalt electrolyte needs particular struct ...

Wiley-Blackwell2015

Synthesis of poly(ethylene-co-butylene)-block-poly(ethylene oxide) surfactant and its use in the synthesis of polyhydroxyethyl methacrylate nanoparticles containing azo-dye

Thomas Geiger, Yee Song Ko

A synthetic path to poly(ethylene-co-butylene)-block-poly(ethylene oxide), a substitute for the "KLE" surfactant was developed. For this purpose, mono hydroxyl end-functionalized poly(ethylene-co-butylene) (similar to 3800 g mol(-1)) was modified with a tr ...

Royal Soc Chemistry2014

Photocatalytic degradation of Remazol Brilliant Blue (R) by sol-gel derived carbon-doped TiO2

Ravindranathan Thampi, Michael Jon Mattle

A simple, cheap and reproducible method to produce a C-doped TiO2 photocatalyst is presented, which can harvest visible light. This doped catalyst is able to degrade a stable organic dye molecule, Remazol Brilliant Blue (R) (RBB), under sunlight and visibl ...

Elsevier Science Bv2013

Multicolor Single Molecule Tracking of Stochastically Active Synthetic Dyes

Suliana Manley, Aleksandr Benke, Julia Gunzenhäuser

Single particle tracking can reveal dynamic information at the scale of single molecules in living cells but thus far has been limited either in the range of potential protein targets or in the quality and number of tracks attainable. We demonstrate a new ...

American Chemical Society2012

Colorants, pile solaire sensibilisée aux colorants et son procédé de fabrication

Michael Graetzel, Mohammad Khaja Nazeeruddin

A dyestuff shown by the formula (1), ML 1 L 2 L 3 (1) wherein M represents an element belonging to Group 8 to Group 10 of the long format Periodic Table, L 1 and L 2 individually represent a bidentate ligand shown by the formula (2), L 3 represents a biden ...

2012

Metabolism of sulphonated anthraquinones in rhubarb, maize and celery: the role of cytochromes P450 and peroxidases

Jean-Paul Schwitzguebel

Sulphonated anthraquinones are precursors of many synthetic dyes and pigments, recalcitrant to biodegradation, and thus contaminating many industrial effluents and rivers. In the development of a phytotreatment to remove sulphonated aromatic compounds, rhu ...

Springer-Verlag2009

Chemical probes shed light on fusion proteins

Kai Johnsson

Site-specific protein labeling with synthetic dyes is an emerging technique for live cell imaging. A protein or peptide tag fused to the protein of interest provides the means for attachment of a fluorophore or other small molecule probe, to allow non-inva ...

2007

Highly dispersed PTFE/Co3O4 flexible films as photocatalyst showing fast kinetic performance for the discoloration of azo-dyes under solar irradiation

Albert Renken, Lioubov Kiwi, Michaël Bensimon, Juan Kiwi, Danièle Laub

Small nanosized clusters of Co3O4 coated on PTFE (polytetrafluoroethylene) flexible film is reported as a novel supported photocatalyst effective in the fast discoloration of the azo-dye Orange II under simulated solar radiation in the presence of oxone (2 ...

2007

Detoxification of diluted azo-dyes at biocompatible pH with the oxone/Co2+ reagent in dark and light processes

Albert Renken, Lioubov Kiwi

Accelerated bleaching and photobleaching of diluted solutions of Methyl Orange and other dyes occur only when Co2+-ions are present in solution mediating oxone (2KHSO(5)center dot KHSO4 center dot K2SO4) decomposition. The bleaching of Methyl Orange, Orang ...

2006