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New dinuclear methoxo-bridged manganese(III) complex [Mn2((MeO-bph) en)2Cl2(μ-CH3O)2] (1) was synthesized by template reaction of 2-hydroxy-4- methoxybenzophenone, 1,2-ethanediamine and MnCl2·6H2O with molar ration (1:1:1) in methanol as solvent. The title compound 1 was characterized by elemental analyses (CHN), Fourier Transform infrared spectroscopy (FT-IR) and single crystal X-ray diffraction. X-ray result reveal that 1 is dimeric with methoxo bridges between two symmetry equivalent manganese ions. The Mn ions are surrounded in a distorted octahedral geometry influenced by Jahn-Teller effect. The tridentate Schiff base ligand MeO-bp-en and one of the methoxo-bridges bind in the equatorial mode, whereas in the axial positions, other metoxo-bridge and Cl atom bind to the Mn ions. Thermogravimetric analysis of 1 was studied and display the title compound 1 decompose in three stages. Finally, by calcination of 1 at 500 °C for 3 h, we prepared Mn2O3 particles and characterized by FT-IR, XRD and SEM. [ABSTRACT FROM AUTHOR]

C14H24Br2N4S2, triclinic, P1‾ $P\overline{1}$ (no. 2), a = 8.1005(2) Å, b = 9.8627(3) Å, c = 12.5984(3) Å, α = 78.038(2)°, β = 84.8290(19)°, γ = 73.203(2)°, V = 942.16(4) Å3, Z = 2, R gt (F 2) = 0.0162, wR ref (F 2) = 0.0486, T = 95 K [1–4].

C13H19Br2N5S2, triclinic, P1‾ $P\overline{1}$ (no. 2), a = 5.22590(10) Å, b = 9.9960(2) Å, c = 17.0076(3) Å, α = 102.1340(15)°, β = 92.9160(16)°, γ = 90.7550(13)°, V = 867.21(3) Å3, Z = 2, R gt(F) = 0.0205, wR ref(F 2) = 0.0737, T = 95 K.

C132H98I12N34O20Zn6, monoclinic, P21 c, a = 34.97800(15) Å, b = 15.02541(6) Å, c = 30.13247(12) Å, β = 101.9033(4)°, V = 15,495.86(11) Å3, Z = 4, R gt(F) = 0.0501, wR ref(F 2) = 0.1329, T = 95 K.

C10H17F6N4OPS2, orthorhombic, P212121 (no. 19), a = 8.7848(9) Å, b = 9.8894(11) Å, c = 18.8020(19) Å, V = 1633.4(3) Å3, Z = 4, Rgt(F) = 0.0348, wRref(F2) = 0.0943, T = 150 K.

C10H17F6N4OPS2, monoclinic, P21/c (no. 14), a = 13.0455(12) Å, b = 12.6114(12) Å, c = 10.7642(10) Å, β = 99.546(8)°, V = 1746.4(3) Å3, Z = 4, Rgt(F) = 0.0425, wRref(F2) = 0.1173, T = 150 K.

This paper addresses the electronic properties of Nd3Ru4Al12 (hexagonal crystal structure) with focus on its magnetic anisotropy that allows a comparison between single-ion and two-ion mechanisms when comparing to U3Ru4Al12. We performed magnetization measurements on a single crystal in static and pulsed magnetic fields as well as neutron-diffraction experiments. Nd3Ru4Al12 is a strongly anisotropic uniaxial ferromagnet with a Curie temperature of 39 K. The magnetic moments are aligned collinearly along the [001] axis. The magnetic structure of Nd3Ru4Al12 has orthorhombic symmetry for which the crystallographic Nd site is split into two magnetically inequivalent positions, Nd1 and Nd2. The Nd1 and Nd2 atoms exhibit reduced magnetic moments, 0.95 and 2.66 μB, as compared to the free Nd3+ -ion value (3.28 μB). We discuss this finding in terms of crystal-field effects and competing exchange and anisotropy interactions. Since the single-ion mechanism in Nd3Ru4Al12 leads to uniaxial anisotropy and the two-ion mechanism of the actinide analog U3Ru4Al12 is known to lead to planar anisotropy, this paper demonstrates the decisive influence of these different mechanisms on the magnetic anisotropy. [ABSTRACT FROM AUTHOR]

Electronic properties of Dy3Ru4Al12 (hexagonal crystal structure, Dy atoms form distorted kagome nets) are studied on a single crystal by means of magnetization, neutron diffraction, specific heat, and resistivity measurements. The onset of a long-range magnetic order of Dy moments occurs at 7 K through a first-order phase transition. The compound has a noncollinear antiferromagnetic structure with a propagation vector (1 /2 0 1/2). The configuration of the Dy moments is consistent with the monoclinic Shubnikov group Cc2/c. The γ coefficient in the temperature linear term of the specific heat is strongly enhanced to 500 mJ mol-1 K-2 taking into account the localized nature of Dy magnetism. An additional contribution originates from spin fluctuations induced in the 4d subsystem of Ruby the exchange field acting from the Dy 4f moments. In an applied magnetic field Dy3Ru4Al12 displays magnetization jumps along all crystallographic directions. All the metamagnetic transitions are accompanied by large positive magnetoresistance. The maximum effect (125%-140%) is attained for current along the [100] axis and field along the [120] or [001] axes. The large positive effect is explained by changes in the conduction electron spectra through the jumps as the conduction electrons interact with localized magnetic moments. [ABSTRACT FROM AUTHOR]

Conventional refinement strategies used for three-dimensional electron diffraction (3D ED) data disregard the bonding effects between the atoms in a molecule by assuming a pure spherical model called the Independent Atom model (IAM) and may lead to an inaccurate or biased structure. Here we show that it is possible to perform a refinement going beyond the IAM with electron diffraction data. We perform kappa refinement which models charge transfers between atoms while assuming a spherical model. We demonstrate the procedure by analysing five inorganic samples; quartz, natrolite, borane, lutecium aluminium garnet, and caesium lead bromide. Implementation of kappa refinement improved the structure model obtained over conventional IAM refinements and provided information on the ionisation of atoms. The results were validated against periodic DFT calculations. The work presents an extension of the conventional refinement of 3D ED data for a more accurate structure model which enables charge density information to be extracted., (© 2024. The Author(s).)

A simple and efficient procedure for synthesizing novel pincer-type tridentate N-heterocyclic carbene bisphenolate ligands is reported. The synthesis of pincer proligands with N , N '-disubstituted imidazoline core, 5 and 6 , was carried out via triethylorthoformate-promoted cyclization of either N , N '-bis(2-hydroxy-3,5-di- tert -butylphenyl)cyclohexanediamine, 3 , or N , N '-bis(2-hydroxyphenyl)cyclohexanediamine, 4 , in the presence of concentrated hydrochloric acid. Cyclic voltammograms of the ligands revealed ligand-centered redox activity, indicating the noninnocent nature of the ligands. The voltammograms of the ligands exhibit two successive one-electron oxidations and two consecutive one-electron reductions. In contrast to previous reports, the redox-active ligands in this study exhibit one-electron oxidation and reduction processes. All products were thoroughly characterized by using 1 H and 13 C NMR spectroscopy. The base-promoted deprotonation of the proligands and subsequent reaction with iron(II) and iron(III) chlorides yielded compounds 7 and 8 . These compounds are binuclear and tetranuclear iron(III) complexes that do not contain carbene functional groups. Complexes 7 and 8 were characterized by using elemental analysis and single-crystal X-ray crystallography. At low catalyst loadings, both 7 and 8 exhibited high catalytic activity in the transfer hydrogenation of selected aldehydes and ketones., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

A starting thiacalix[4]arene can be easily transformed into oxidized phenoxathiin-based macrocycles 9 and 9', representing an unusual structural motif in calixarene chemistry. The presence of electron-withdrawing groups (SO 2 , SO) and the considerable internal strain caused by the condensed heterocyclic moiety render these molecules susceptible to nucleophilic attack. The reaction with various organolithium reagents provides a number of different products resulting from the cleavage of either the calixarene skeleton or the phenoxathiin group or both ways simultaneously. This enables the preparation of thiacalixarene analogues with unusual structural features, including systems containing a biphenyl fragment as a part of the macrocyclic skeleton. The above-described transformations, unparalleled in classical calixarene chemistry, clearly demonstrate the synthetic potential of this thiacalixarene subgroup., Competing Interests: There are no conflicts of interest to declare., (This journal is © The Royal Society of Chemistry.)

A novel octahedral distorted coordination complex was formed from a copper transition metal with a bidentate ligand (1,10-Phenanthroline) and characterized by Ultraviolet-visible spectroscopy, Ultraviolet-visible diffuse reflectance spectroscopy, Fourier-transform infrared spectroscopy, Brunauer-Emmett-Teller, Field emission scanning electron microscopy, and Single-crystal X-ray diffraction. The Hirshfeld surface and fingerprint plot analyses were conducted to determine the interactions between atoms in the Cu(II) complex. DFT calculations showed that the central copper ion and its coordinated atoms have an octahedral geometry. The Molecular electrostatic potential (MEP) map indicated that the copper (II) complex is an electrophilic compound that can interact with negatively charged macromolecules. The HOMO-LUMO analysis demonstrated the π nature charge transfer from acetate to phenanthroline. The band gap of [Cu(phen) 2 (OAc)]·PF 6 photocatalyst was estimated to be 2.88 eV, confirming that this complex is suitable for environmental remediation. The photocatalytic degradation of erythrosine, malachite green, methylene blue, and Eriochrome Black T as model organic pollutants using the prepared complex was investigated under visible light. The [Cu(phen) 2 (OAc)]·PF 6 photocatalyst exhibited degradation 94.7, 90.1, 82.7, and 74.3 % of malachite green, methylene blue, erythrosine, and Eriochrome Black T, respectively, under visible illumination within 70 min. The results from the Langmuir-Hinshelwood kinetic analysis demonstrated that the Cu(II) complex has a higher efficiency for the degradation of cationic pollutants than the anionic ones. This was attributed to surface charge attraction between photocatalyst and cationic dyes promoting removal efficiency. The reusability test indicated that the photocatalyst could be utilized in seven consecutive photocatalytic degradation cycles with an insignificant decrease in efficiency., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Coupling of electron-deficient urea units with aliphatic chains gives rise to amphiphilic compounds that bind to phosphate and benzoate anions in the hydrogen bonding competitive solvent (DMSO) with K Ass = 6 580 M -1 and K Ass = 4 100 M -1 , respectively. The anchoring of these receptor moieties to the dendritic support does not result in a loss of anion binding and enables new applications. Due to the formation of a microenvironment in the dendrimer, the high selectivity of the prepared compound toward benzoate is maintained even in the presence of aqueous media during extraction experiments. In the presence of binding sites at 5 mM concentration, the amount of benzoate corresponding to the full binding site occupancy is transferred into the chloroform phase from its 10 mM aqueous solution. A thorough investigation of the extraction behavior of the dendrimer reported here, supported by a series of molecular dynamics simulations, provides new insight into the fundamental principles of extraction of inorganic anions by amphiphiles., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)

Derivatization of (NHC)M-Cl (M = Ag, Au) with selected sulfur donors from the family of dialkyldithiophosphates and bis(2-mercapto-1-methylimidazolyl)borate ligands gave a series of heteroleptic mononuclear complexes. In single-crystal X-ray diffraction analysis, Ag(I) complexes adopted a trigonal planar geometry, while Au(I) complexes are near-linear. TD-DFT and hole-electron analyses of the selected complexes gave insight into the electronic features of the metal complexes. In vitro cellular tests were conducted on the human cancerous breast cell line MCF-7 using 2 and 8 . The antibacterial activities of complexes 1 , 2 , 3 , 7 , 8 , and IPr-Ag-Cl were also screened against Gram-positive ( Staphylococcus aureus PTCC 1112) and Gram-negative ( Escherichia coli PTCC 1330) bacteria. Antityrosinase and hemolytic effects of the selected compounds were also determined.

Pillar[ n ]arenes are among the newest members of the macrocyclic family. Nevertheless, their conformational behavior and binding properties as well as redox properties of dealkylated pillar[ n ]arenes are well-studied. At the same time, introducing a heteroatom into a cyclophane macrocycle is already known to alter all the above properties drastically. This study presents a simple synthetic approach based on thia-Michael addition cyclization that readily resulted into hexathiapillar[6]arene with four phenylene units alternated by two redox-active hydroquinone moieties. The straightforward synthesis of the macrocycle enabled a systematic study of its conformation and redox behavior. The modification of hexathiapillar[6]arene afforded five functionalized derivatives, which were studied structurally in detail. The findings revealed interesting redox and structural properties of the macrocycle and its derivatives including the formation of crystal lattices with continuous channels and empty voids.

Chlorinated paraffins (CPs) are a notoriously known class of compounds that stand amongst the most wide-spread persistent organic pollutants. Therefore, their reliable, repeatable, and reproducible quantitative analysis using well-defined reference standards is of utmost importance. In view of the increasing demand for constitutionally and stereochemically defined CP standards, we have synthesized a stereoisomeric mixture of 3,4,7,8-tetrachlorodecane. One stereoisomer - (3 R ,4 R ,7 S ,8 S )-3,4,7,8-tetrachlorodecane was separated from the mixture, and enriched fractions of residual stereoisomers were achieved through crystallisation of the residual mother liquors. The molecular structure of the single isolated stereoisomer was confirmed through single-crystal X-ray crystallographic data. One fraction of 3,4,7,8-tetrachlorodecane stereoisomers was successfully separated on a chiral stationary phase using supercritical fluid chromatography hyphenated to mass spectrometry (column: Chiral ART Amylose-C; mobile phase: CO 2 /MeOH (96/4 v/v) with 0.1% diethylamine). The reported separation of stereoisomers is unprecedented in CP analysis so far., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Authors.)

The role of bridging and terminal ligand electronic and steric properties on the structure and antiproliferative activity of two-coordinated gold(I) complexes was investigated on seven novel binuclear and trinuclear gold(I) complexes synthesized by the reaction of either Au 2 (dppm)Cl 2 , Au 2 (dppe)Cl 2 , or Au 2 (dppf)Cl 2 with potassium diisopropyldithiophosphate, K[(S-O i Pr) 2 ], potassium dicyclohexyldithiophosphate, K[(S-OCy) 2 ], or sodium bis(methimazolyl)borate, Na(S-Mt) 2 , which afforded air-stable gold(I) complexes. In 1 - 7 , the gold(I) centers adopt a two-coordinated linear geometry and are structurally similar. However, their structural features and antiproliferative properties highly depend upon subtle ligand substituent changes. All complexes were validated by 1 H, 13 C{ 1 H}, 31 P NMR, and IR spectroscopy. The solid-state structures of 1 , 2 , 3 , 6 , and 7 were confirmed using single-crystal X-ray diffraction. A density functional theory geometry optimization calculation was used to extract further structural and electronic information. To investigate the possible cytotoxicities of 2 , 3 , and 7 , in vitro cellular tests were carried out on the human cancerous breast cell line MCF-7. 2 and 7 show promising cytotoxicity., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)

A new mixed-ligand Cu(II) complex formulated as [Cu(dipic)(amp)(H 2 O)].H 2 O (dipic: pyridine-2,6-dicarboxylic acid, amp: 2-amino-4-methylpyridine), was synthesized and structurally characterized by FTIR spectroscopy, CHN analysis, and the single-crystal X-ray crystallographic method. The complex crystallizes in an orthorhombic space group Pna2 1, and the coordination environment around the metal center was found to be a pentacoordinate CuN 2 O 2 O W distorted square-pyramidal geometry. In order to systematically explore a detailed in vitro and in silico study of the DNA binding of the title complex, various biophysical (UV-Vis absorption spectroscopy, fluorescence, competitive binding with ethidium bromide) and theoretical (DFT, molecular docking simulation, and QM/MM) methods were applied which revealed that the complex could intercalate with the insertion of the amp ligand between the DNA base pairs. The experimental thermodynamic parameters of the interaction revealed the spontaneity of the process and the domination of the hydrophobic interactions in the association and stabilization of the DNA-Cu(II) complex adduct, which was in line with the docking and QM/MM data. In vitro cytotoxic potential of the complex against the human breast adenocarcinoma (MCF-7) cells was examined using MTT assay, which indicated that cancerous cells showed inhibition in presence of the complex., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)