scholarly journals Coordination Compounds Featuring Non-Toxic Chiral 1,4-Dicarboxylic Acids and Copper(II)

Crystals ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 485
Author(s):  
Marius Kremer ◽  
Jan van Leusen ◽  
Ulli Englert
Keyword(s):  
Tartaric Acid ◽  
Coordination Compounds ◽  
Divalent Cations ◽  
Dicarboxylic Acids ◽  
Water Soluble ◽  
Environmentally Benign ◽  
Mononuclear Complexes ◽  
Oxygen Coordination ◽  
Jahn Teller ◽  
Copper Cations

Six new coordination compounds of copper cations and 1,4-dicarboxylic acids have been synthesized and structurally investigated. Aspartic acid (H2asp), enantiopure, racemic and meso tartaric acid (H2tart), di-para-toluyltartaric acid (H2dptta) and dibenzoyltartaric acid (H2dbta) represent environmentally benign water-soluble proligands which may be deprotonated for oxygen coordination. Chelating ligands such as tetramethylethylenediamine (TMEDA) and 2-aminomethylpyridine (AMPY) efficiently reduce the dimensionality of the target compounds, and additional aqua ligands complete the coordination environments. In this line of argument, the discrete mononuclear complexes [Cu(AMPY)(asp)(H2O)] and [Cu(Hdbta)2(H2O)4] were obtained; for the latter, only a preliminary structure model can be presented which, however, agrees with the powder diffraction pattern of the bulk. From enantiopure and racemic tartaric acid and TMEDA the closely related chain polymers [CuII(H2tart)(TMEDA)(H2O)2)]n were obtained; the racemic compound consists of individual homochiral strands of opposite chirality. The high steric demand of di-para-toluyltartaric acid leads to one-dimensional [Cu(dptta)(EtOH)(H2O)2]n with coordinated ethanol (EtOH) in the distant Jahn–Teller site of the coordination sphere. Cu(II), meso-tartaric acid and TMEDA aggregate to a trinuclear coordination compound [CuII2CuI(H2tart)(Htart)(TMEDA)2]. Its peripheral cations show the expected Jahn–Teller geometry of Cu(II), but the unambiguous assignment of the oxidation state +I for central cation required susceptibility measurements: their results prove the presence of only two and only very weakly interacting divalent cations, separated by a diamagnetic center.

scholarly journals THE SYNTHESIS OF COPPER(II)-CONTAINING 1,2,4-TRIAZOLE COMPLEXES

2017 ◽  
pp. 35-36
Author(s):  
I. Petrenko ◽  
D. Khomenko ◽  
R. Doroschuk ◽  
R. Lampeka
Keyword(s):  
Coordination Compounds ◽  
Coordination Complexes ◽  
Octahedral Complex ◽  
Tetragonal Symmetry ◽  
X Ray Diffraction ◽  
X Ray ◽  
Mononuclear Complexes ◽  
Jahn Teller ◽  
Jahn Teller Effect ◽  
Metal Ligand

Methods of the synthesis of the copper(II) containing 3-(2-pyridinyl)-1H-1,2,4-triazole complexes are reported. Systematic studies were devoted to the investigating an importance of triethylamine towards the сomplexation. The various coordination modes that have been observed in complexes were discussed. We noticed the correlations of coordination complexes structure and the metal-ligand correlation. Two mononuclear complexes and one dinuclear complex of a 2:2 composition were obtained. The deprotonation of the ligand in the complex namely [Cu(L)2](H2O)2 was eased by adding triethylamine. The octahedral complex [Cu(HL)2(NO3)](NO3) was synthesized without triethylamine. In excess of ligands, mononuclear coordination compounds formed mostly. By adding the equal to ligand amount of triethylamine we obtained complex in a lower tetragonal symmetry. Deprotonated triazole is the high field ligand, therefore, due to the Jahn–Teller effect, square coordination is more desirable. In all coordination compounds formation of the 5-membered chelate cycle realizes through a pyridine-triazole binding site.The structures of three complexes have been determined by single crystal X-ray diffraction.

Environmentally benign and cost-effective synthesis of water soluble red light emissive gold nanoclusters: selective and ultra-sensitive detection of mercuric ions

2019 ◽  
Vol 43 (2) ◽  
pp. 900-906 ◽  
Author(s):  
Aniruddha Kundu ◽  
Byeongho Park ◽  
Chaiti Ray ◽  
Juyeong Oh ◽  
Seong Chan Jun
Keyword(s):  
Red Light ◽  
Gold Nanoclusters ◽  
Cost Effective ◽  
Water Soluble ◽  
Environmentally Benign ◽  
Sensitive Detection ◽  
Green Approach ◽  
Effective Synthesis ◽  
Mercuric Ions

A green approach to synthesize red emissive gold nanoclusters for nano-molar detection of mercuric ions.

Molecular characteristics of water-soluble dicarboxylic acids, ω-oxocarboxylic acids, pyruvic acid and α-dicarbonyls in the aerosols from the eastern North Pacific

2020 ◽  
Vol 224 ◽  
pp. 103812
Author(s):  
Mir Md. Mozammal Hoque ◽  
Kimitaka Kawamura ◽  
Tomohiro Nagayama ◽  
Bhagawati Kunwar ◽  
Edward T. Peltzer ◽  
...  
Keyword(s):  
Pyruvic Acid ◽  
North Pacific ◽  
Dicarboxylic Acids ◽  
Water Soluble ◽  
Molecular Characteristics ◽  
Oxocarboxylic Acids

Synthesis, thermal stability, electronic features, and antimicrobial activity of phenolic azo dyes and their Ni(II) and Cu(II) complexes

2014 ◽  
Vol 68 (3) ◽  
Author(s):  
Selma Bal ◽  
Sedat Bal ◽  
Abdullah Erener ◽  
Hatice Halipci ◽  
Seyhan Akar
Keyword(s):  
Thermal Stability ◽  
Antimicrobial Activity ◽  
Antifungal Activity ◽  
Azo Dyes ◽  
Coordination Compounds ◽  
Decomposition Temperature ◽  
Water Soluble ◽  
The Other ◽  
Spectroscopic Methods ◽  
Antimicrobial And Antifungal Activity

AbstractFour water soluble azo dyes, 4-(isopropyl)-2-[(E)-(4-chlorophenyl)diazenyl]phenol (L 1), 4-(isopropyl)-2-[(E)-(2,4-dichlorophenyl)diazenyl]phenol (L2), 4-(sec-butyl)-2-[(E)-(4-chlorophenyl) diazenyl]phenol (L 3), 4-(sec-butyl)-2-[(E)-(2,4-dichlorophenyl)diazenyl]phenol (L 4), and their Cu(II) and Ni(II) complexes were synthesized and characterized using spectroscopic methods. Examination of their thermal stability revealed similar decomposition temperature of approximately 260–300°C and that they were more thermally stable than their metal complexes. Ni(II) complexes of ligands L2 and L4 were more stable than the other coordination compounds. Among the synthesized ligands, L2 and the complexes Cu(L3)2 and Ni(L4)2 showed both antimicrobial and antifungal activity. However, the other ligands and the complexes were poorly active against selected microorganisms.

scholarly journals Long-Range Transport Mechanisms in East and Southeast Asia and Impacts on Size-Resolved Aerosol Composition: Contrasting High and Low Aerosol Loading Events

2019 ◽  
Author(s):  
Rachel A. Braun ◽  
Mojtaba Azadi Aghdam ◽  
Paola Angela Bañaga ◽  
Grace Betito ◽  
Maria Obiminda Cambaliza ◽  
...  
Keyword(s):  
Long Range ◽  
Biomass Burning ◽  
Dicarboxylic Acids ◽  
Organic Aerosol ◽  
Water Soluble ◽  
Long Range Transport ◽  
Aerosol Loading ◽  
Range Transport ◽  
Metro Manila ◽  
East And Southeast Asia

Abstract. This study analyzes mechanisms of long-range transport of aerosol and aerosol chemical characteristics in and around East and Southeast Asia. Ground-based size-resolved aerosol measurements collected at the Manila Observatory in Metro Manila, Philippines from July–October 2018 were used to identify and contrast high and low aerosol loading events. Multiple data sources, including models, remote-sensing, and in situ measurements, are used to analyze the impacts of long-range aerosol transport on Metro Manila and the conditions at the local and synoptic scales facilitating this transport. Evidence of long-range transport of biomass burning aerosol from the Maritime Continent was identified through model results and the presence of biomass burning tracers (e.g. K, Rb) in the ground-based measurements. The impacts of emissions transported from continental East Asia are also identified; for one of the events analyzed, this transport was facilitated by the nearby passage of a typhoon. Changes in the aerosol size distributions, water-soluble chemical composition, and contributions of various organic aerosol species to the total water-soluble organic aerosol were examined for the different cases. The events impacted by biomass burning transport had the overall highest concentration of water-soluble organic acids, while the events impacted by long-range transport from continental East Asia, showed high percent contributions from shorter chain dicarboxylic acids (i.e. oxalate) that are often representative of photochemical and aqueous processing in the atmosphere. The low aerosol loading event was subject to a larger precipitation accumulation than the high aerosol events, indicative of wet scavenging as an aerosol sink in the study region. This low aerosol event was characterized by a larger relative contribution from supermicrometer aerosols and had a higher percent contribution from longer-chain dicarboxylic acids (i.e. maleate) to the water-soluble organic aerosol fraction. Results of this study have implications for better understanding of the transport and chemical characteristics of aerosol in a highly-populated region that has thus far been difficult to measure through remote-sensing methods. Furthermore, findings associated with the effects of air mass mixing on aerosol physiochemical properties are applicable to other global regions impacted by both natural and anthropogenic sources.

scholarly journals Aircraft observations of water-soluble dicarboxylic acids in the aerosols over China

2016 ◽  
Author(s):  
Yan-Lin Zhang ◽  
Kimitaka Kawamura ◽  
Ping Qing Fu ◽  
Suresh K. R. Boreddy ◽  
Tomomi Watanabe ◽  
...  
Keyword(s):  
Oxalic Acid ◽  
Organic Compounds ◽  
Aqueous Phase ◽  
Dicarboxylic Acids ◽  
Liquid Water Content ◽  
Water Soluble ◽  
Aircraft Observations ◽  
Volatile Organic ◽  
Intercontinental Transport ◽  
Surface Measurements

Abstract. Vertical profiles of low molecular weight dicarboxylic acids, related organic compounds and SOA tracer compounds in particle phase have not yet been simultaneously explored in East Asia, although there is growing evidence that aqueous phase oxidation of volatile organic compounds may be responsible for the elevated organic aerosols (OA) in the free troposphere. Here, we found consistently good correlation of oxalic acid, the most abundant organics globally, with its precursors as well as biogenic-derived secondary OA (SOA) compounds in Chinese tropospheric aerosols by aircraft measurements. Anthropogenically derived dicarboxylic acids (i.e., C5 and C6 diacids) at high altitudes were 4–20 times higher than those from surface measurements and even occasionally dominant over oxalic acid at altitude higher than 2 km, which is in contrast to the predominance of oxalic acid previously reported globally including the tropospheric and surface aerosols. This indicates an enhancement of tropospheric SOA formation from anthropogenic precursors. Furthermore, oxalic acid-tosulfate ratio maximized at altitude of ~2 km, explaining aqueous-phase SOA production that was supported by good correlations with predicted liquid water content, organic carbon and biogenic SOA tracers. These results demonstrate that elevated oxalic acid and related SOA compounds from both the anthropogenic and biogenic sources may substantially contribute to tropospheric OA burden over polluted regions of China, implying aerosol-associated climate effects and intercontinental transport.

scholarly journals Vertical distribution of particle-phase dicarboxylic acids, oxoacids and α-dicarbonyls in the urban boundary layer based on the 325-meter tower in Beijing

2020 ◽  
Author(s):  
Wanyu Zhao ◽  
Hong Ren ◽  
Kimitaka Kawamura ◽  
Huiyun Du ◽  
Xueshun Chen ◽  
...  
Keyword(s):  
Boundary Layer ◽  
Oxalic Acid ◽  
Vertical Distribution ◽  
Organic Acids ◽  
Anthropogenic Activities ◽  
Ground Surface ◽  
Dicarboxylic Acids ◽  
Ground Level ◽  
Water Soluble ◽  
Motor Vehicles

Abstract. Vertical distribution of dicarboxylic acids, oxoacids, α-dicarbonyls, and other organic tracer compounds in fine aerosols (PM2.5) was investigated from the ground surface (8 m) to 260 m at a 325-meter meteorological tower in Beijing in the summer of 2015. Results showed that the concentrations of oxalic acid (C2), the predominant diacid, were more abundant at 120 m (210 ± 154 ng m−3) and 260 m (220 ± 140 ng m−3) than those at the ground level (160 ± 90 ng m−3). Concentrations of phthalic acid (Ph) decreased with the increase of heights, demonstrating that the vehicular exhausts at the ground surface was the main contributor. Positive correlations were noteworthy for C2/total diacids with mass ratios of C2 to main oxoacids (Pyr, ωC2) and α-dicarbonyls (Gly, MeGly) in polluted days (0.42 ≤ r2 ≤ 0.65), especially at the ground level. In clean days, the ratios of carbon content in oxalic acid to water soluble organic carbon (C2-C/WSOC) showed larger values at 120 m and 260 m than those at the ground surface. However, in polluted days, the C2-C/WSOC ratio mainly reached its maximum at the ground level. These phenomena may indicate the enhanced contribution of aqueous-phase oxidation to oxalic acid in polluted days. Combined with the influence of wind field, total diacids, oxoacids and α-dicarbonyls decreased by 22 %–58 % under the control on anthropogenic activities during the 2015 Victory Parade period. Furthermore, the PMF results showed that the secondary formation routes (secondary sulfate formation and secondary nitrate formation) were the dominant contributors (37–44 %) to organic acids, followed by biomass burning (25–30 %) and motor vehicles (18–24 %). In this study, the organic acids at the ground level were largely associated with local traffic emissions, while the long-range atmospheric transport followed by photochemical aging contributed more to diacids and related compounds in the boundary layer over Beijing than the ground surface.

scholarly journals Optimization of Environmentally Benign Polymers Based on Thymine and Polyvinyl Sulfonate Using Plackett-Burman Design and Surface Response

2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Julieta Ledesma ◽  
Santiago A. Bortolato ◽  
Carlos E. Boschetti ◽  
Débora M. Martino
Keyword(s):  
Integrated Circuits ◽  
Ph Effect ◽  
Dye Adsorption ◽  
Water Soluble ◽  
Environmentally Benign ◽  
Copolymer Films ◽  
Adsorption Processes ◽  
Burman Design ◽  
Traditional Approaches ◽  
Plackett Burman Design

Traditional approaches to the development of integrated circuits involve the use and/or manufacture of toxic materials that have a potential environmental impact. An extensive research has been done to design environmentally benign synthetic polymers containing nucleic acid bases, which can be used to enhance the photoresistor technologies. Water soluble, environmentally benign photopolymers of 1-(4-vinylbenzyl) thymine (VBT) and vinylphenyl sufonate (VPS) undergo a photodimerization reaction when exposed to low levels of ultraviolet irradiation leading to an immobilization of the copolymer on a variety of substrates. Plackett-Burman design (PBD) and central composite design (CCD) were applied to identify the significant factors influencing the polymer crosslinking and dye adsorption processes, which are relevant in the fabrication of copolymer films for potential photoresist use. The PBD results assigned a maximum absorption signal of 0.67, while optimal conditions obtained in this experiment following the CCD method predictions provided a response of 0.83 ± 0.03, being a solid foundation for further use of this methodology in the production of potential photoresistors. The pH effect was relevant for low concentrations but not significant for higher concentrations. To the best of our knowledge, this was the first report applying statistical experimental designs to optimize the crosslinking of thymine-based polymers.

Acceptorless dehydrogenative condensation of o-aminobenzamides with aldehydes to quinazolinones in water catalyzed by a water-soluble iridium complex [Cp*Ir(H2O)3][OTf]2

2015 ◽  
Vol 2 (12) ◽  
pp. 1589-1597 ◽  
Author(s):  
Feng Li ◽  
Lei Lu ◽  
Juan Ma
Keyword(s):  
Water Soluble ◽  
Environmentally Benign ◽  
Iridium Complex

A general, efficient and environmentally benign method for the synthesis of quinazolinones via acceptorless dehydrogenative condensation of o-aminobenzamides with aldehydes in water has been accomplished.

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