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1
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Epoxy resin modified with amine as an effective complexing agent of metal cations

100%
Kurczewska J., Schroeder G.
Open Chemistry
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2013
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vol. 11
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issue 11
1723-1728
EN
A simple synthesis of a material capable of metal cation removal is proposed. The material was a derivative of epoxy resin containing amine groups. It is insoluble in water and in this study it was characterized by elemental analysis and infrared spectroscopy. The sorbent obtained was tested for its ability to remove coper(II), cadmium(II) and lead(II) from water solutions. The tests were performed for different concentrations of metal ions (10–200 mg L−1) and at different pH (2.0–9.0). The effects of temperature and stirring time, as well as reusability of the sorbent were also studied in batch experiments. In the optimum conditions, the decrease in the cation concentration in aqueous solutions was observed in the order Cu>Pb>Cd but for each ion the decrease was at least 50% of the initial concentration. The sorbent has demonstrated high effectiveness in cation sorption and after regeneration it can be applied repeatedly in the process described. [...]
2
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Modified silica surface by phenylboronic acid derivatives as effective sugar sensor

100%
Kurczewska J., Schroeder G.
Open Chemistry
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2009
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vol. 7
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issue 4
697-701
EN
Silica surface was modified with phenylboronic acid derivatives. The structures of the functionalized supports were characterized by FT-IR spectroscopy, 13C CP/MAS NMR spectrometry, elemental and thermogravimetric analysis. The solid supports were effectively applied as artificial receptors for sugars in aqueous solutions. Alizarin Red S. (ARS) was used to detect colour change upon carbohydrate (sugar) binding. The association constants of the supports studied-ARS complex and the functionalized silica-sugar (glucose) complex were calculated. The parameters obtained were comparable with those for the phenylboronic acids used for the silica gel modification. The competitive binding of the functionalized silica surface with ARS and sugar were studied by UV/VIS measurements. [...]
3
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Chemistry for nanotechnology

100%
Schroeder G., Kurczewska J.
Polish Journal of Chemical Technology
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2014
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vol. 16
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issue 1
70-74
EN
In recent years, the processing order during the synthesis of new chemical compounds has been redefined. Until now a chemist considered primarily receiving a new compound and only then searched for its potential application. The new philosophy of proceedings forces chemists to answer the question: what physical and chemical properties a new chemical compound must have, and what should be structured. After that it has to be planned how to get the compound including the defined budget. The compounds obtained by conventional chemical synthesis are then used to create new functional materials having the properties as scheduled. The paper presents the way of the proceedings from a molecular receptor to a new nanomaterial containing this receptor, so in other words from individual molecules to new material with specific and previously planned properties.
4
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The bifunctionality of silica gel modified with Congo red

100%
Kurczewska J., Schroeder G.
Open Chemistry
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2011
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vol. 9
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issue 1
41-46
EN
Silica gel was chemically modified with Congo red and characterized by Fourier transform infrared spectroscopy, elemental and thermogravimetric analysis. The pH-sensitive immobilized Congo red retains the same properties as its solution counterpart and could be applied as solid indicator. The functionalized silica gel was also employed to extract different cations from water solutions. The concentration of cations extracted was determined by inductively coupled plasma optical emission spectrometry. The solid support is able to selectively extract silver and copper from water solutions and retains its properties after treatment with different organic and inorganic solvents. [...]
5
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Remediation of heavy metals from soil using quartz sand functionalized with organic amino silanes

81%
Grzesiak P., Łukaszyk J., Schroeder G., Kurczewska J.
Polish Journal of Chemical Technology
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2013
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vol. 15
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issue 4
116-120
EN
The results of the research studies concerning the binding of heavy metals (HMs) by quartz sand functionalized with amino silanes have been described. The studies have been carried out on soils sampled from the areas affected by emissions from Copper Smelter and Refinery. The research aims to increase the food safety in the areas of industrial impact. The presence of polyamine chain in the hybrid materials obtained enables a binding of heavy metals (nickel, copper, cobalt). The best results are observed for the hybrid material having four amine groups (four coordination centers) per molecule. For this material the highest content after two extraction cycles (pH 7.0 and 5.0) is observed for copper (98.2%), but for other ions (nickel, cobalt) it is at least 85% of the initial amount of components available for plants.
6
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Copper removal by carbon nanomaterials bearing cyclam-functionalized silica

81%
Kurczewska J., Schroeder G., Narkiewicz U.
Open Chemistry
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2010
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vol. 8
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issue 2
341-346
EN
The synthesis of metal (Fe, Co, Ni)-encapsulated carbon nanomaterials coated with cyclam-bonded silica has been described. The organic layer was identified by Fourier transform infrared spectroscopy and elemental analysis. The functionalized magnetic nanomaterials were employed to extract the divalent cations: copper, calcium, cobalt, manganese and nickel from aqueous solutions. Their adsorption capacities were studied by the batch procedure. The concentration of cations extracted was determined by inductively coupled plasma mass spectrometry. Influence of different parameters viz. pH, amount of the compound studied, contact time, on the cation extraction was investigated. Under optimum conditions copper extraction was significantly more efficient when compared with other coexisting ions. [...]
7
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Binding of Industrial Deposits of Heavy Metals and Arsenic in the Soil by 3-Aminopropyltrimethoxysilane

81%
Grzesiak P., Łukaszyk J., Schroeder G., Kurczewska J.
Polish Journal of Chemical Technology
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2014
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vol. 16
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issue 2
12-15
EN
The results of the research studies concerning binding of heavy metals and arsenic (HM+As), occurring in soils affected by emissions from Głogów Copper Smelter and Refinery, by silane nanomaterial have been described. The content of heavy metals and arsenic was determined by AAS and the effectiveness of heavy metals and arsenic binding by 3-Aminopropyltrimethoxysilane was examined. The total leaching level of impurities in those fractions was 73.26% Cu, 74.7% – Pb, 79.5% Zn, 65.81% – Cd and 55.55% As. The studies demonstrated that the total binding of heavy metals and arsenic with nanomaterial in all fractions was about as follows: 20.5% Cu, 9.5% Pb, 7.1% Zn, 25.3% Cd and 10.89% As. The results presented how the safety of food can be cultivated around industrial area, as the currently used soil stabilization technique of HM by soil pH does not guarantee their stable blocking in a sorptive complex.
8
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Bifunctional sulfur-silicon podands as new nucleophilic ionophores in acyl transfer reactions. Influence of monovalent cations on the reaction kinetics

81%
ŁLęska B., Schroeder G., Gierczyk B., Rybachenko V.
Open Chemistry
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2006
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vol. 4
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issue 2
351-362
EN
Two bifunctional sulfur-silicon nucleophilic ionophores 3-(trimethoxysilyl)-propanethiol (Nu1) and 3-(tri-2-methoxyethoxysilyl)-propanethiol (Nu2) were used as reagents in the acyl transfer reaction studied by kinetic methods. Nuclear magnetic resonance (NMR) and electro-spray ionisation mass spectrometry (ESI MS) were used for determination of the stoichiometry and stability constants of the complexes made by the podands and lithium or sodium ions in acetonitrile solution.
9
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Immobilization of quaternary ammonium salts on silica gel for perchlorate ions removal

81%
Kurczewska J., Pankiewicz R., Schroeder G.
Open Chemistry
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2012
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vol. 10
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issue 5
1452-1458
EN
Silica surface was modified with quaternary ammonium salts to give three matrices of different chain length. The synthesized supports were characterized by elemental analysis and infrared spectroscopy, as well as scanning electron microscopy and semi-empirical parametric method 5. Their exchange capacities for ClO4−, F−, NO3− and CH3COO− ions were investigated by conductometric titration. The amount of exchanged chloride ions from the matrix was studied for different initial anions concentration. The functionalized silica gel showed very good ability of perchlorate ions exchange from the water solution in room temperature. The anion-exchange properties were also studied in comparison to different number of reactive sites in the matrices. The increased number of chloride at the silica surface took effect on increased ability of ClO4− anion exchange [...]
10
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Impact of selected supramolecular additives on the initial electrochemical lithium intercalation into graphite in propylene carbonate

81%
Walkowiak M., Waszak D., Gierczyk B., Schroeder G.
Open Chemistry
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2008
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vol. 6
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issue 4
600-606
EN
Impact of silicon tripodand-type electrolyte additives and graphite pre-treatment agents on the electrochemical intercalation of lithium cations into graphite was investigated. Addition of Si-tripodand-type silanes to propylene carbonate-based electrolytes was found to suppress detrimental solvent co-intercalation and graphite exfoliation. Similar effects were observed for graphite pre-treated with the reported silane agents. It was observed that the presented supramolecular additives allow for the formation of effective passive layers on graphite during first charging, and thus can be considered as novel low-cost film-forming components for rechargeable lithium batteries. [...]
11
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Adsorption studies and release of selected dyes from functionalized mesoporous MCM-41 silica

81%
Lewandowski D., Olejnik A., Schroeder G.
Open Chemistry
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2014
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vol. 12
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issue 2
233-241
EN
Functionalized mesoporous MCM-41 silica was subjected to adsorption and release studies of encapsulated guest molecules of three chosen dyes. These mesoporous systems were composed of three different capping reagents introduced by grafting method on the silica surface to control the release of dye molecules at two different pH values. The amounts of dyes adsorbed on the silica surface were measured using ultraviolet-visible (UV-VIS) spectrophotometry. The efficiency of grafting was calculated on the basis of differential thermal analysis (TG) results and elemental analysis. The release profiles were determined for all obtained systems using USP Dissolution Apparatus 2. Adsorption of the two azo dyes used was the most efficient after the positively charged functionalization and lower after functionalization with neutral and negatively charged capping reagents, while the phthalocyanine dye adsorption was almost functionalization-independent. Grafting efficiency was the highest for neutral capping reagent and much lower for electrically charged molecules of other reagents. Release studies showed clearly that desorption was pH-dependent for azo dyes and pH independent for Alcian Blue. The adsorption and release seem to be connected with the electrical charge of all constituents of these systems. Results obtained can be used for further analysis of different electrically charged molecules.
12
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The risk scale estimation of the agricultural environment pollution by heavy metals using the sequential extraction method

81%
Rosada J., Grzesiak J., Schroeder G.
Polish Journal of Chemical Technology
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2007
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vol. 9
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issue 3
151-154
EN
From among various industrial contaminants which can pollute agricultural environment, heavy metals having the capacity of bioaccumulation deserve special attention. The total composition analysis of the heavy metals content in the polluted soils does not provide enough data about their accessibility to the crops cultivated on these soils. It is very important to have the information about the forms in which the examined element exists, because it decides about its mobility and toxicity for the environment. Using the sequential chemical extraction method of Zeien and Brümmer the fractions of Cu, Pb, Zn, Cd and As in the soils influenced by emissions from the Copper Smelter GŁOGÓW, were investigated. The aim of these investigations was to determine the availability assessment of the mentioned elements to the crops cultivated in this region.
13
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1H NMR and spectrophotometric study of alkaline metal ion complexes with N-dansyl aza-18-crown-6

62%
Ossowski T., Sulowska1 H., Karbowiak T., Zarzeczanska D., Gierczyk B., Schroeder G.
Open Chemistry
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2006
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vol. 4
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issue 1
13-28
EN
Formation of complexes of A18C6-Dns and metal cations (Ca2+, Sr2+, Ba2+ and Mg2+) in acetonitrile has been studied by NMR, absorption and fluorescence spectroscopy and PM5 semi-empirical methods. A18C6-Dns forms stable complexes with Ca2+, Sr2+ and Ba2+ cations. The stability constants of various complexes are determined by different methods and their structures are visualised by the PM5 semi-empirical calculations.
14
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Copper complexes formed by 3,5-bis(2,2′-bipyridin-4-ylethynyl)benzoic acid and its methyl and ethyl esters as studied by electrospray ionization mass spectrometry

62%
Frański R., Kowalska M., Czerniel J., Zalas M., Gierczyk B., Cegłowski M., Schroeder G.
Open Chemistry
|
2013
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vol. 11
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issue 12
2066-2075
EN
Electrospray ionization mass spectrometry was used to study the complexes of ligands containing two bipyridine units, namely 3,5-bis(2,2-bipyridin-4-ylethynyl)benzoic acid (1) and its methyl and ethyl esters (2, 3), with copper cation, with CuCl2 as a source of copper. It was found that the type of complexes formed strongly depends on CuCl2 concentration. At lower CuCl2 concentration, the detected complexes were rather simple and some of them were formed upon electrospray ionization conditions e.g. ions [22+Cu2]2+ and [32+Cu2]2+ (complexes ligand-Cu(I) of stoichiometry 2:2) which are analogical to the well known, for quaterpyridine, helical complexes. At higher CuCl2 concentration, the detected complexes were more complicated, and most of them contained copper cations bridged by chlorides. The largest ions were [L2+Cu4Cl6]2+. The CID MS/MS spectra of these ions allowed determination of their mass spectrometric fragmentation pathways and as a consequence their structure elucidation. [...]
15
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Unexpected formation of [M]2+from [M+CuCl+H]2+ions under CID conditions, where M is a molecule of 3,5-bis(2,2’-bipyridin-4-ylethynyl)benzoic acid or its methyl ester

62%
Frański R., Zalas M., Gierczyk B., Cegłowski M., Schroeder G., Kozik T., Hoffmann M.
Open Chemistry
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2015
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vol. 13
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issue 1
EN
[M+CuCl+H]2+ ions were generated using electrospray ionization (ESI); where M is a molecule of 3,5-bis(2,2’-bipyridin-4-ylethynyl)benzoic acid or its methyl ester (1 and 2, respectively). The ions were subjected to CID-MS/MS analysis. It was found that their gas phase decomposition lead to the formation of rare di-cations [M]2+, namely [1]2+ and [2]2+ ions. The formation of [1]2+ ion from [3+H+CuCl]2+ ion in the second fragmentation, where 3 is ethyl ester of 3,5-bis(2,2-bipyridin-4-ylethynyl)benzoic acid, was also observed since in the first fragmentation step the loss of ethylene molecule from [3+H+CuCl]2+ ion took place. To the best of our knowledge, it is the first time that [M]2+ ions formation from respective metal complexes has been reported. It is also unusual that formation of [M]2+ ions is not accompanied by formation of [M]+∙ ions. Furthermore, as expected, theoretical calculation and electron ionization mass spectra show that 1 and 2 are not especially prone to form [M]2+ ions. Thus formation of [M]2+ ions under CID conditions is very surprising.
16
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Biomass of freshwater Cladophora as a raw material for agriculture and the cosmetic industry

62%
Messyasz B., Leska B., Fabrowska J., Pikosz M., Roj E., Cieslak A., Schroeder G.
Open Chemistry
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2015
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vol. 13
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issue 1
EN
This study was undertaken to determine mineral content, amino acid and fatty acid composition of the freshwater macroalga – Cladophora glomerata. The studies were based on the content comparison in algal biomass collected from a lake and cultured in a laboratory. To determine the ability of copper cumulating by macroalgae, Cladophora was cultured in the medium supplemented with Cu ions. This study indicated that the relative abundance of metals in filaments decreased in the following order: Ca > K > Mg > Na > Fe > Cu > Zn > Pb > As > Ni > Cd > Mn > Cr > Co. Total protein content ranged from 14.45% in Cladophora from a lake to 26.55% in Cladophora from a laboratory. The main amino acids analyzed were aspartic and glutamic acid. The fatty acid content in the dry matter of the extract varied depending on the extraction method used: ethylene alcohol (19.0%), acetone (34.5%) or supercritical fluid extraction (62.5%). Freshwater C. glomerata due to the macrominerals, trace elements, amino and fatty acids composition in the extracts can be a valuable resource for nutritional and cosmetic applications.
17
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Effects of organic compounds on the macroalgae culture ofAegagropila linnaei

62%
Messyasz B., Leska B., Fabrowska J., Pikosz M., Cieslak A., Schroeder G.
Open Chemistry
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2015
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vol. 13
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issue 1
EN
The effects of the impact of four organic compounds (ascorbic acid, biotin, glucose and sucrose) on ash, protein, fiber, fat and amino acid contents in the freshwater Aegagropila linnaei biomass were examined in 7 and 14 days of cultivations in high concentrations of tested compounds (100 mg L-1). The presence of examined organic compounds had a negligible effect on the development of algae and their biomass composition. There were no significant differences in the amino acids composition in the biomass in the presence of organic compounds compared to the test system. However, the increase in ash content was observed irrespective of the cultivation time in the case of all used organic compounds. Only slight differences in crude fat concentration were observed in the case of 7 days cultivation with ascorbic acid, biotin and sucrose, while the highest increase of ash content was observed after 14 days of supplementation with glucose. None of the compounds affected changes in amino acid content in the Aegagropila linnaei biomass. The results suggest that an environment enriched with the test organic compounds had only minimal, or at most short-term, effects on the algal biomass composition.
18
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FAPA mass spectrometry of hydroxychalcones. Comparative studies with classical methods of ionization

62%
Smoluch M., Bartkowiak G., Reszke E., Lechowicz W., Silberring J., Schroeder G.
Current Issues in Pharmacy and Medical Sciences
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2014
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vol. 27
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issue 1
27-31
EN
In this paper we are focused on analysis of hydroxychalcones, i.e. 2’-hydroxychalcone, 3’-hydroxychalcone and 4’-hydroxychalcone, by the Flowing Atmospheric Pressure Afterglow mass spectrometry (FAPA-MS), and on comparison of the obtained data with other classical methods including ESI-MS, APCI, MALDI, and GC/EI-MS. The paper is presenting fragmentation pathways of both positive-, and negative hydroxychalcone ions. Tested compounds were characterized by comparison of the results (signals m/z and relative intensities) from the five mass spectrometry techniques, showing very good utility of FAPA method for fast and easy analysis of the low molecular weight compounds. Moreover, FAPA does not require a time-consuming derivatization, nor search for a suitable solvent or matrix, often incompatible with various ion sources.
19
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Electrospray ionization mass spectrometric study of mercury complexes of N-heterocyclic carbenes derived from 1,2,4-triazolium salt precursors

62%
Frański R., Gierczyk B., Schroeder G., Pieper S., Springer A., Linscheid M.
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EN
By mixing 1,2,4-triazolium salts (precursors of N-heterocyclic carbenes 1–6) with mercury acetate, a number of complexes have been obtained under electrospray ionization condition. Carbenes 1 and 2 contain one carbene center; therefore, they are able to bond only one mercury cation. Carbenes 3–5 contain two carbene centers; therefore, they can bond two mercury cations. Mercury complexes of 1–5 always contain an acetate anion attached to a mercury cation. Carbene 6 also contains two carbene centers; however, its structure allows formation of a complex containing mercury bonded simultaneously to both centers, therefore, the complex that does not contain an acetate anion. The MS/MS spectra taken for complexes of carbenes 1–5 have shown formation of a cation corresponding to N1 substituent (adamantyl or benzyl), and those of complexes of carbenes 3–5 (doubly charged ions) have also shown the respective complementary partner ions. Mercury complex of 2 has yielded some other interesting fragmentation pathways, e.g. a loss of the HHgOOCCH3 molecule. The fragmentation pathway of the mercury complexes of 6 was found to be complicated.
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