Supplementary material for the article: Wang, L.; Zlatar, M.; Vlahović, F.; Demeshko, S.; Philouze, C.; Molton, F.; Gennari, M.; Meyer, F.; Duboc, C.; Gruden, M. Experimental and Theoretical Identification of the Origin of Magnetic Anisotropy in Intermediate Spin Iron(III) Complexes. Chemistry - A European Journal 2018, 24 (20), 5091–5094. https://doi.org/10.1002/chem.201705989

Supplementary material for: [https://doi.org/10.1002/chem.201705989]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2130

An air-persistent oxyallyl radical cation with simple di(methyl)amino substituents

International audienc

Study of the Direct Red 81 Dye/Copper(II)-Phenanthroline System

Recovered papers contain several chromophores, such as wood lignin and dyes. These have to be eliminated during paper recycling in order to produce white paper. Hydrogen peroxide under alkaline conditions is generally used to decolorize lignin, but its effect on dyes is limited. Copper(II)-phenanthroline (Cu-Phen) complexes can activate the oxidation of lignin by hydrogen peroxide. Hydrogen peroxide may also be activated during recycled fiber bleaching, thus enhancing its color-stripping efficiency towards unoxidizable azo dyes. The purpose of this paper was to determine the effect of Cu-Phen complexes on a model azo dye, Direct Red 81 (DR81), in aqueous solution. Different Cu-Phen solutions (with different initial Cu:Phen molar ratios) were prepared and mixed with the dye at different pHs. The geochemical computer program PHREEQC allowed precise calculation of the theoretical distribution between different possible coordinates (CuPhenOH+, Cu(Phen)22+, CuPhen(OH)2, Cu(Phen)32+, etc.) depending on pH and initial concentrations. UV-vis spectroscopic measurements were correlated with the major species theoretically present in each condition. The UV absorbance of the system was mainly attributed to the Cu-Phen complex and the visible absorbance was only due to the dye. Cu-Phen appeared to reduce the color intensity of the DR81 dye aqueous solution under specific conditions (more effective at pH 10.7 with Cu:Phen = 1:1), probably owing to the occurrence of a coordination phenomenon between DR81 and Cu-Phen. Hence, the ligand competition between phenanthroline and hydroxide ions would be disturbed by a third competitor, which is the dye molecule. Further investigation proved that the DR81 dye is able to form a complex with copper-phenanthroline, leading to partial color-stripping. This new “color-stripping effect” may be a new opportunity in paper and textile industries for wastewater treatment

Catalyse homogène efficace de la réduction électrochimique de l'oxyde nitreux en diazote sur des catalyseurs de type rhénium-carbonyle

International audienceWe show that reduced rhenium bipyridyl carbonyl complexes are stable and selective catalysts for deoxygenation of nitrous oxide (N2O) in organic media in the presence of water. Mechanistic studies indicate that the Re complex is initially reduced to produce the activated species. N2O then binds to labile position at the reduced metal and the resulting adduct is further reduced to trigger N–O bond breaking and release of N2. Proton donors are beneficial to enhance the catalytic rate and to reduce the energy required to generate potential limiting intermediate. These results open directions for N–O bond activation.Dans cette publication, nous montrons que les complexes réduits de rhénium bipyridylcarbonyle sont des catalyseurs stables et sélectifs pour la désoxygénation du protoxyde d'azote (N2O) en milieu organique en présence d'eau. Des études mécanistiques indiquent que le complexe Re est initialement réduit pour produire l'espèce catalytique active. Le N2O se coordine ensuite au métal réduit et complexe résultant est encore réduit pour déclencher la rupture de la liaison N-O et la libération de N2. La présence de donneurs de protons est bénéfique pour améliorer l'efficacité catalytique et pour réduire l'énergie requise pour générer l'intermédiaire réactionnel limitant. Ces résultats ouvrent des perspectives pour l'activation de la liaison N-O

Chemical modification of N-methylphenothiazine to lead to interesting and potential organic material for lithium battery

International audienceHuman activity generates an environmental impact increasingly important including in the field of transport and portable electronics. It is therefore essential to develop of new technologies capable of producing and storing electrical energy. In this context, organic material based battery can constitute an interesting alternative compared to inorganic ones. Less costly and toxic and allowing to involve other alkali cation (rather than Li+), since few years such materials are evoked in literature. However, their performance yet do not compete with that of involving inorganic cathodic material (i.e. Lithium iron phosphate). In this context, multi electron process can be the way to reach high performance organic compounds. This can be done using phenothiazine which, through an adapted chemical modification, can undergo a two electron oxidation in the potential window stability of classical electrolyte. This work is dedicated to the impact of N-methyl-phenothiazine chemical modification on its electrochemical behavior. The stability of oxidized forms of modified phenothiazine is investigated helping to select the best monomer to be involved as cathodic polymer material in battery

[Mn(bipyridyl)(CO)3Br]: An Abundant Metal Carbonyl Complex as Efficient Electrocatalyst for CO2 Reduction

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Hydroxyl Radical Generation by the H2O2/CuII/Phenanthroline System under Both Neutral and Alkaline Conditions: An EPR/Spin-Trapping Investigation

The copper–phenanthroline complex CuI(Phen)2 was the first artificial nuclease studied in biology. The mechanism responsible for this activity involves CuII(Phen)2 and H2O2. Even if H2O2/Cu systems have been extensively studied in biology and oxidative chemistry, most of these studies were carried out at physiological pH only, and little information is available on the generation of radicals by the H2O2/CuII-Phen system. In the context of paper pulp bleaching to improve the bleaching ability of H2O2, this system has been investigated, mostly at alkaline pH, and more recently at near-neutral pH in the case of dyed cellulosic fibers. Hence, this paper aims at studying the production of radicals with the H2O2/CuII-Phen system at near-neutral and alkaline pHs. Using the EPR/spin-trapping method, HO• formation was monitored to understand the mechanisms involved. DMPO was used as a spin-trap to form DMPO–OH in the presence of HO•, and two HO• scavengers were compared to identify the origin of the observed DMPO–OH adduct, as nucleophilic addition of water onto DMPO leads to the same adduct. H2O2 decomposition was enhanced by the addition of CuII–Phen (and only slightly by addition of CuSO4), reaching a level similar to the Fenton reagent at near-neutral pH. This evidences the role of Phen, which improves the effect of CuII by tuning the electronic structure and structural properties of the corresponding CuII complexes

Hydroxyl Radical Generation by the H₂O₂/Cu^II/Phenanthroline System under Both Neutral and Alkaline Conditions: An EPR/Spin-Trapping Investigation

The copper–phenanthroline complex CuI(Phen)2 was the first artificial nuclease studied in biology. The mechanism responsible for this activity involves CuII(Phen)2 and H2O2. Even if H2O2/Cu systems have been extensively studied in biology and oxidative chemistry, most of these studies were carried out at physiological pH only, and little information is available on the generation of radicals by the H2O2/CuII-Phen system. In the context of paper pulp bleaching to improve the bleaching ability of H2O2, this system has been investigated, mostly at alkaline pH, and more recently at near-neutral pH in the case of dyed cellulosic fibers. Hence, this paper aims at studying the production of radicals with the H2O2/CuII-Phen system at near-neutral and alkaline pHs. Using the EPR/spin-trapping method, HO• formation was monitored to understand the mechanisms involved. DMPO was used as a spin-trap to form DMPO–OH in the presence of HO•, and two HO• scavengers were compared to identify the origin of the observed DMPO–OH adduct, as nucleophilic addition of water onto DMPO leads to the same adduct. H2O2 decomposition was enhanced by the addition of CuII–Phen (and only slightly by addition of CuSO4), reaching a level similar to the Fenton reagent at near-neutral pH. This evidences the role of Phen, which improves the effect of CuII by tuning the electronic structure and structural properties of the corresponding CuII complexes

From blind spot into the spotlight: editorial to the special issue 'Light, lighting, and human behaviour'

Light stimulates vision, and a growing body of knowledge shows that the environment thus revealed affects mood, health, and cognition. Recent neurological and biological discoveries of non-visual processes stimulated by light have spurred a wealth of research in those areas, but these processes are as behavioural, and therefore psychological, as they are physiological. Lighting research is an interdisciplinary activity, one that we think should attract greater attention from environmental psychologists. This editorial outlines the underlying processes through which light and lighting influence behaviour, and describes the diverse articles in the special issue. Collectively, the papers in this special issue convey the message that light and lighting deserve more attention from psychologists; rather than being a fringe topic, it should be near the heart of the domain of environmental psychology.Peer reviewed: YesNRC publication: Ye

CO2 to CO Electroreduction, Electrocatalytic H2 Evolution, and Catalytic Degradation of Organic Dyes Using a Co(II) meso-Tetraarylporphyrin

The meso-tetrakis(4-(trifluoromethyl)phenyl)porphyrinato cobalt(II) complex [Co(TMFPP)] was synthesised in 93% yield. The compound was studied by 1H NMR, UV-visible absorption, and photoluminescence spectroscopy. The optical band gap Eg was calculated to 2.15 eV using the Tauc plot method and a semiconducting character is suggested. Cyclic voltammetry showed two fully reversible reduction waves at E1/2 = −0.91 V and E1/2 = −2.05 V vs. SCE and reversible oxidations at 0.30 V and 0.98 V representing both metal-centred (Co(0)/Co(I)/Co(II)/Co(III)) and porphyrin-centred (Por2−/Por−) processes. [Co(TMFPP)] is a very active catalyst for the electrochemical formation of H2 from DMF/acetic acid, with a Faradaic Efficiency (FE) of 85%, and also catalysed the reduction of CO2 to CO with a FE of 90%. Moreover, the two triarylmethane dyes crystal violet and malachite green were decomposed using H2O2 and [Co(TMFPP)] as catalyst with an efficiency of more than 85% in one batch