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Salamo‐type ligand H2L was designed and synthesized and reacted with Cu (II) and Zn (II) acetate, respectively, to obtain two binuclear Cu (II) and Zn (II) complexes: [Cu2(L)2]·2CH3OH (1) and [Zn2(L)2] (2) having the same coordination number but distinct geometries. Complex 1 is a Cu (II) complex containing two crystalline ethanol molecules, where two Cu (II) atoms are surrounded by two utterly deprotonated (L)2− parts, forming slightly twisted tetragonal pyramidal configurations of pentacoordinate. In complex 2, two utterly deprotonated (L)2− parts surround two Zn (II) atoms, forming pentadentate twisted triangular bipyramidal configurations. The complexes were elucidated via IR analyses and ultraviolet spectroscopy. Using DFT theoretical calculation, MEPs, IRI, and Hirshfeld surface analysis to investigate further the molecular interactions and reaction sites. Ultimately, the fluorescence characteristics of H2L and its complexes 1 and 2 were discussed. [ABSTRACT FROM AUTHOR]

Two novel tetra‐ and hepta‐nuclear Ni(II) salamo‐type clusters, [Ni4(L)2(μ2‐Cl)2(μ3‐OH)2(EtOH)2]⋅4CH2Cl2 (1) and [Ni7(L)3(μ3‐OEt)2(μ3‐OH)6(EtOH)2] (2), were constructed by modulating different anions (Cl− and NO3−). X‐ray crystallographic researches revealed that cluster 1 is a tetranuclear cluster consisting of a symmetric binuclear structure in which chloride ions are involved in coordination. Although cluster 2 consists of seven Ni(II) ions, three deprotonated (L)2− parts, two μ3‐ethoxy groups, six μ3‐OH− anions, and two coordinated ethanol molecules, in which it is quite rare for a large number of water molecules to be deprotonated to participate in the bridging of the cluster due to the alkaline environment. TEM electron scanning displayed the distinct shapes. Comparison of DFT calculations revealed that cluster 2 is less chemically reactive and more kinetically stable, which is in accordance with the analytical results of weak interactions, where the stronger weak interaction forces were presented, the more stable the molecule is. Finally, a comparative analysis of UV–Vis, IR, and fluorescence spectra were carried out. [ABSTRACT FROM AUTHOR]

Maintaining the geometrical stability of hot filament is a challenge in chemical vapor deposition (CVD) over a larger area since deformation varies the distance between the filament and the substrate and, consequently, destroys the uniformity of diamond deposition. Herein, Ta filament is straightened with a tensile stress ranging from 4.40 to 11 MPa to suppress deformation, and the stability during the CVD process of diamond film is evaluated. Scanning electron microscopy and energy dispersive X‐ray are further utilized to investigate the morphological and structural evolutions of Ta filament. Results show that straightened Ta filament maintains geometrical stability without any visible deformation or breakage and uniform deposition of diamond film is obtained through Ta filament undergone a transformation from Ta to Ta2C and then to TaC. At high deposition pressure (7 kPa) or a low concentration of methane (1%), the straightened Ta filament goes through a moderate transformation, which implies the cracks caused by rough transformation can be avoided, thus prolonging the lifetime of straightened Ta filament. These works provide significant guidelines for the large‐scale manufacture of diamond deposition. [ABSTRACT FROM AUTHOR]

Axially chiral N-arylindoles bearing a stereogenic C-N axis are unique important scaffolds in natural products, advance materials, pharmaceuticals and privileged chiral ligands or catalysts. Herein, we report the direct synthesis of C-N axially chiral N-arylindoles through a Pd-catalyzed free amine-directed atroposelective C-H olefination enabled by a spiro phosphoric acid (SPA) ligand. A wide range of enantioenriched N-aromatic amine indoles were obtained in high yields with good enantioselectivities (35 examples, up to 91% yield and up to 96% ee). The chiral products with free amine group offer an effective functional handle for down-stream diversity-oriented synthesis. [ABSTRACT FROM AUTHOR]

Acetate‐bridged binuclear Co(II) and Ni(II) complexes, [Co2(L)(μ‐OAc)(EtOH)] (1) and [Ni2(L)(μ‐OAc)(EtOH)] (2) were synthesized via the reaction of a new bis(salamo)‐like ligand with two different metal(II) acetates. X‐ray single crystal diffraction analyses showed that two metal(II) ions (Co or Ni) occupy two sets of N2O2 cavities, respectively. The acetate group bridges the two metals, and the ethanol oxygen atom participates in the coordination. Furthermore, UV–vis titration experiments clearly indicated that the complexation between H3L and M(II) ions leads to the 1:2 complexes [(L)M2]+ through a highly synergistic process. Bond valence sum (BVS) calculations exhibited that the Co(II) and Ni(II) ions are divalent. Secondly, the ligand H3L highest occupied molecular orbital–lowest unoccupied molecular orbital (HOMO‐LUMO) gap analysis and surface electrostatic potential were theoretically analyzed by theoretical calculation (density functional theory), and the reactivity of M(II) ions and the ligand in the complex formation process was demonstrated. Finally, the microscopic properties of the complexes were deeply understood through the calculation of the weak intramolecular interactions and the unstressed regions outside the complexes. [ABSTRACT FROM AUTHOR]

While functional materials with both light transmitting and electromagnetic shielding are highly desirable and have made rapid advancements, only very few of them meet the stringent electromagnetic interference (EMI) shielding criteria for optoelectronic systems. Achieving high optical transparency and superior EMI shielding in a broad frequency spectrum is a remaining challenge in both academic and industrial areas. Herein, a design strategy of shorted micro‐waveguides (SMWs) array to decouple the light transmission and EMI shielding is proposed and experimentally demonstrated. The array of SMWs, consisting of cutoff metallic micro‐waveguides and shorting indium tin oxide (ITO) continuous conductive film, exhibits high optical transmittance of 90.4% and superior EMI shielding effectiveness of 60.8 dB on average over ultra‐wide frequency spectrum (0.2–1.3 GHz & 1.7–18 GHz). Compared to previously reported works, an improvement of 17 dB in average shielding effectiveness is achieved under the same level of light transmission, and the shielding frequency spectrum is significantly expanded. The working principle is explained in depth and factors influencing the performance are investigated for design optimization. These outstanding properties enable the transparent shielding material based on SMWs to excel in future applications of EMI shielding for optoelectronic systems. [ABSTRACT FROM AUTHOR]

Two helical centrosymmetric homotetranuclear Cu (II) complexes, [Cu4(L)2(EtOH)2](ClO4)2·2EtOH·2CHCl3(1) and [{Cu4(L)2(EtOH)2}{Cu4(L)2(HNO3)2}](NO3)4·3EtOH·3MeOH (2), were synthesized by the reactions of a symmetric bis (salamo)‐based ligand H3L with Cu(ClO)2·6H2O and Cu(NO)3·3H2O, respectively, and certified by elemental analyses, UV–Visible absorption spectra, infrared spectra and single‐crystal X‐ray analysis techniques. X‐ray crystal structure analyses reveal that four Cu (II) atoms of complex 1 are attached to two deprotonated ligand (L)3− units with the help of two coordinated ethanol molecules, and then forming a helical centrosymmetric complex by H‐bonding and π⋯π interactions. While complex 2 unit cell contains two crystallographically independent but chemically identical homotetranuclear complexes (molecules A and B), eight Cu (II) atoms are coordinated by four deprotonated ligand (L)3− units. The coordination mode of four Cu (II) atoms from molecule A is the same as complex 1; at the same time, oxygen atoms on nitrates are involved in the coordination of another four Cu (II) atoms from molecule B. The short‐range interactions in complexes 1 and 2 were calculated by Hirshfeld surfaces analyses. The molecular orbital energy levels, molecular stabilities of complexes 1 and 2 were analyzed by DFT calculations. In addition, antibacterial assays were also investigated in detail. [ABSTRACT FROM AUTHOR]

Two novel homomultinuclear complexes [Co6(L)2(μ‐OAc)4]·2CHCl3·CH3COCH3 (1) and [Ni2(L)(H2O)2(Py)2]·2CHCl3 (2) with a newly designed rigid bis(salamo)‐type tetraoxime ligand (H4L) were synthesized and characterized by elemental analyses, Fourier transform infrared (FT‐IR) spectra, UV–Vis absorption spectra, and X‐ray single‐crystal diffractions. Complex 1 is a novel triple‐decker symmetrical six‐core cluster structure with twofold axis and inversion center. The Co(II) atoms were sandwiched between the bis(salamo)‐type ligands and possess two different geometries of distorted tetragonal pyramid and octahedron, respectively. Complex 2 possesses a dinuclear structure and the Ni(II) atoms are located in the N2O2 cavities of the ligand, and axial coordination atoms come from the coordinated water and pyridine molecules. Both Ni(II) atoms adopt distorted octahedral geometries. The interactions were quantitatively determined by Hirshfeld surfaces analyses of complexes 1 and 2. The coordination ratios were determined by studying the fluorescence properties of complexes 1 and 2. The results of fluorescence titration experiment show that the metals to ligand binding ratios are 6:2 and 2:1 for complexes 1 and 2, respectively. [ABSTRACT FROM AUTHOR]

Two dinuclear Ni (II) and Zn (II) salamo‐type complexes, [Ni2(L)(μ‐OAc)(MeOH)]·2CHCl3 (1) and [{Zn2(L)(μ‐OMe)}3]·3CHCl3·MeOH (2), have been successfully synthesized by wet‐chemical method and characterized by elemental analyses, IR spectra, UV–Vis spectra and single crystal X‐ray diffraction. Complex 1 consists of two closely related dinuclear units 1A and 1B, and complex 2 consists of three closely related dinuclear units 2A, 2B and 2C. The five units are unique example of crystallographically independent but chemically identical molecules. The Ni (II) atoms of complex 1 are located in the N2O4 coordination cavities, possessing six‐coordinated distorted octahedral geometries, but all Zn (II) atoms in complex 2 are located in the N2O3 coordination cavities, possessing five‐coordinated distorted square‐pyramid and triangular bipyramid geometries, the geometries about the Zn (II) atoms (Zn3 and Zn6) that obtain in 2B and 2C where τ5 is very close to 0.500, which is τ5Zn3 = 0.5006 and τ5Zn6 = 0.4941, respectively. The interactions were quantitatively determined by Hirshfeld surfaces analyses. Significantly, fluorescence properties were also investigated. [ABSTRACT FROM AUTHOR]

An unprecedented enantioselective synthesis of spiro‐γ‐lactams via a sequential C−H olefination/asymmetric [4+1] spirocyclization under a simple CoII/chiral spiro phosphoric acid (SPA) binary system is reported. A range of biologically important spiro‐γ‐lactams are obtained with high levels of enantioselectivity (up to 98 % ee). The concise, asymmetric synthesis of an aldose reductase inhibitor was successfully achieved. Notably, contrast to previous reports that relied on the use of cyclopentadienyl or its derivatives (achiral Cp*, CptBu, or chiral Cpx) ligated CoIII complexes requiring tedious steps to prepare, cheap and commercially available cobalt(II) acetate tetrahydrate was used as an efficient precatalyst. [ABSTRACT FROM AUTHOR]

A family of rare structurally different homometal multinuclear CuII bis(salamo)‐based complexes, [Cu4(L)2(MeOH)2](ClO4)2·2MeOH (1), [Cu4(L)2(EtOH)2](NO3)2·2EtOH (2) and [Cu2(HL)(EtOH)Br2]·CHCl3 (3), has been successfully synthesized by the reactions of cupric salts with a bis(salamo)‐based multidentate chelate ligand (H3L). The salamo‐based ligand [R‐CH=N—O—(CH2)n—O—N=CH—R] is a new type of salen‐based analog. Complexes (1) and (2) are isostructural structures, and crystallize in monoclinic space group P21/n with centrosymmetric spiral structures, where the main structures contain two fully deprotonated ligand (L)3− units, a charged tetranuclear CuII folding center and two coordinated solvent molecules. Complex (3) crystallizes in monoclinic space group Cc and consists of two CuII cations, one incompletely deprotonated ligand (HL)2− unit and one coordinated ethanol molecule, and forms a novel homo‐binuclear CuII complex structure due to Br− counter anions. Complexes (1)–(3) have zero‐dimensional cluster‐based structures and are further assembled into three‐dimensional frameworks via intermolecular interactions. Because of the different solvents and counter anions which have a significant influence on the structures of complexes (1)–(3), the interactions were quantitatively evaluated by Hirshfeld surfaces analyses. Complexes (1)–(3) have been characterized by elemental analyses, IR spectra, UV–vis spectra and X‐ray crystallography analyses. In addition, fluorescence properties are evaluated and DFT calculations are performed. [ABSTRACT FROM AUTHOR]

Using symmetrical bis (salamo)‐type tetraoxime ligand H3L and Cu (ClO4)2·6H2O in different solvent systems, two unusual homomultinuclear Cu (II) complexes, [Cu4(L)2(CH3CH2OH)2](ClO4)2·2H2O (1) and [Cu2(L)]n (ClO4)n·nCH3CN (2), were synthesized and characterized by single‐crystal X‐ray diffraction analyses, elemental analyses, infrared (IR), ultraviolet–visible (UV–Vis) spectroscopy, Hirshfeld surfaces analyses, and density functional theory (DFT) calculations. Complex 1 includes [Cu4(L)2(CH3CH2OH)2]2+ ion, two ClO4− counter anions, two coordinated ethanol molecules and two aquatic dissociative molecules, the two deprotonated ligand (L)3− units package around four Cu (II) ions yield a centrosymmetric helical molecules with a charged linear folding center, while complex 2 forms a 1‐D linear topology structure and is only the substitution of chloroform in the solvent system of complex 1 with acetonitrile. Coordination mode of complex 2 is widely different from that of complex 1. In the Cu (II) ions of complex 1, there are two coordination modes of Cu (II) ions, the hexa‐coordinated distorted octahedral structure and the penta‐coordinated distorted tetragonal pyramid structure, but complex 2 only has almost perfect tetragonal pyramid geometry. Fluorescence properties of H3L and its complexes 1 and 2 have also been explored. [ABSTRACT FROM AUTHOR]

Two newly designed heteromultinuclear [CuII4SmIII2] and [CuII2TbIII] bis (salamo)‐based complexes, [{Cu2(L)Sm (NO3)2(μ2‐NO3)(CH3OH)}2]·2CH3OH and [Cu2(L)Tb (NO3)2(μ2‐NO3)][Cu2(L)Tb (NO3)2(μ2‐NO3)(H2O)]·CH3OH, were synthesized and characterized by elemental analyses, Fourier transform infrared (FT‐IR) spectra, ultraviolet–visible (UV–vis) absorption spectra, and X‐ray crystallography. The ultraviolet titration experiments exhibited that the coordination ratio of the ligand, rare earth metal, and transition metal is 1:1:2. In the [CuII4SmIII2] complex, Cu1 atom has a distorted quadrilateral pyramid geometry, whereas Cu2 atom forms a slightly distorted octahedral geometry. The [CuII2TbIII] complex unit cell contains two crystallographically independent and chemically different heterotrinuclear complexes (Molecules A and B). In Molecule A, the Cu1 atom bears a four‐coordinated plane quadrilateral geometry, whereas the five‐coordinated Cu2 atom forms a slightly distorted tetragonal cone geometry. In Molecule B, the five‐coordinated Cu3 and Cu4 atoms possess slightly distorted tetragonal cone geometries. Noncovalent interactions like hydrogen bonding and π···π stacking interactions are operative in construction of supramolecular architectures. The [CuII2TbIII] complex behaves as a catalyst towards oxidative coupling of 2‐AP in MeCN medium. In addition, fluorescence properties of the ligand H4L and its [CuII4SmIII2] and [CuII2TbIII] complexes have also been discussed. [ABSTRACT FROM AUTHOR]

To (i) introduce the technical notes of a novel full‐endoscopic foraminotomy with a large endoscopic trephine for the treatment of severe degenerative lumbar foraminal stenosis at L5S1 level; (ii) assess the primary clinical outcomes of this technique; (iii) compare the effectiveness of this full‐endoscopic foraminotomy technique and other previous techniques for lumbar foraminal stenosis. From January 2019 to August 2019, a retrospective study of L5S1 severe degenerative lumbar foraminal stenosis was performed in our center. All patients who were diagnosed with severe foraminal stenosis at L5S1 level and failed conservative treatment for at least 6 weeks were identified. Patients with segmental instability or other coexisting contraindications were excluded. A total of 21 patients were enrolled in the study. All patients were treated by full‐endoscopic foraminotomy using large endoscopic trephine. The visual analogue scale (VAS) and Oswestry disability index (ODI) were evaluated preoperatively and at 1, 3, 6 months, and 1 year after the surgery, and the modified MacNab criteria were used to evaluate clinical outcomes at the last follow‐up. There were 10 males and 11 females with a mean age of 66.38 ± 9.51 years. Five patients had a history of lumbar surgery. The mean operative time was 63.57 ± 25.74 min. The mean follow‐up time was 13.29 ± 1.38 months. The mean postoperative hospital stay time was 1.29 ± 0.56 days. The mean preoperative VAS score significantly decreased from 7.38 ± 1.02 to 2.76 ± 1.09 (t = 19.759, P < 0.01), 2.25 ± 1.02 (t = 21.508, P < 0.01), 1.60 ± 1.05 (t = 31.812, P < 0.01), and 1.45 ± 1.10 (t = 25.156, P < 0.01) at 1 month, 3 months, 6 months, and 1 year after the operation. The mean preoperative ODI score significantly decreased from 64.66% ± 4.91% to 30.69% ± 4.59% (t = 33.724, P < 0.01), 29.44% ± 4.50% (t = 32.117, P < 0.01), 24.22% ± 4.14% (t = 33.951, P < 0.01), and 22.44% ± 4.94% (t = 30.241, P < 0.01) at 1 month, 3 months, 6 months, and 1 year after the operation. At the last follow‐up, 19 patients (90.48%) got excellent or good outcomes. One patient suffered postoperative dysesthesia, and the symptoms were controlled by conversion treatment. One patient took revision surgery due to the incomplete decompression. There were no other major complications. Percutaneous endoscopic decompression is minimally invasive spine surgery. However, the application of endoscopic decompression for L5S1 foraminal stenosis is relatively difficult due to the high iliac crest and narrow foramen. Full‐endoscopic foraminotomy with the large endoscopic trephine is an effective and safe technique for the treatment of degenerative lumbar foraminal stenosis. [ABSTRACT FROM AUTHOR]

Three novel multinuclear NiII complexes, namely, bis{μ‐2‐methoxy‐6‐[8‐(pyridin‐2‐yl)‐3,6‐dioxa‐2,7‐diazaocta‐1,7‐dien‐1‐yl]phenolato}bis[thiocyanatonickel(II)], [Ni2(L)2(NCS)2], 1, bis{μ‐2‐methoxy‐6‐[8‐(pyridin‐2‐yl)‐3,6‐dioxa‐2,7‐diazaocta‐1,7‐dien‐1‐yl]phenolato}bis[azidonickel(II)], [Ni2(L)2(N3)2], 2, and catena‐poly[[{2‐methoxy‐6‐[8‐(pyridin‐2‐yl)‐3,6‐dioxa‐2,7‐diazaocta‐1,7‐dien‐1‐yl]phenolato}nickel(II)]‐μ‐dicyanamidato], [Ni(L)(dca)]n, 3 {dca is dicyanamide, C2N3, and HL is 2‐methoxy‐6‐[8‐(pyridin‐2‐yl)‐3,6‐dioxa‐2,7‐diazaocta‐1,7‐dien‐1‐yl]phenol, C16H17N3O4}, with a half‐salamo‐based pyridine‐containing HL ligand have been synthesized and characterized by FT–IR, UV–Vis absorption spectroscopy, X‐ray crystallography, Hirshfeld surface analysis and density functional theory (DFT) calculations. The central NiII ions in complexes 1–3 are hosted in the half‐salamo‐based N3O‐donor cavity of the organic ligand. Complex 1 is a centrosymmetric dimer and two [Ni(L)(NCS)] units form a centrosymmetric dimeric structure, which is bridged by two phenolate O atoms. The two N atoms at the axial ends are provided by two NCS− ligands. In complex 1, each NiII ion has a six‐coordinated octahedral geometry. Complex 2 is similar to 1, but they differ in that the auxiliary NCS− ligand is replaced by N3−. However, complex 3 is a one‐dimensional coordination polymer constructed from [Ni(L)(dca)] units, which are connected by the auxiliary bidentate dca ligand viaN‐donor atoms. As with complexes 1 and 2, the NiII ion in 3 has a six‐coordinated octahedral geometry. [ABSTRACT FROM AUTHOR]

An asymmetric salamo‐based probe molecule (H2L) was synthesized and characterized structurally. When DMF/H2O (9:1) was used as the solvent, it was shown probe H2L has high sensitivity to Cu2+. Using high‐resolution mass spectrometry and theoretical calculation, it was found that probe H2L could form a more stable complex (1:1) with Cu2+, the minimum limit of detection (LOD) of H2L for Cu2+ was calculated as 9.95 × 10−8 M. In addition, probe H2L could also be used to identify B4O72− under the same detection conditions and the minimum LOD of H2L for B4O72− was calculated as 4.98 × 10−7 M. At the same time, density functional theory theoretical calculation further proved the flexibility of probe H2L. Through the action of EDTA, probe H2L had a cyclic ability to recognize Cu2+, and showed a better response in the physiological pH range; probe H2L had the characteristics of fast recognition speed and high efficiency. In addition, with probe H2L test paper for Cu2+ and B4O72−, the effect was more obvious. Meanwhile, probe H2L can be used to quantitatively detect Cu2+ in water samples. [ABSTRACT FROM AUTHOR]

Two new tetranuclear NiII complexes, [Ni4(L1)2(N3)4(MeOH)2]·CH3COCH3(1) and [Ni4(L2)2(N3)4(MeOH)2]·4CH3COCH3(2), were synthesized using NiCl2·6H2O, NaN3, and asymmetric salamo‐based ligands H2L1 and H2L2, respectively. The structural characterization was made by elemental analyses, infrared (IR) and ultraviolet‐visible (UV‐vis) spectra, and X‐ray diffraction analyses. The results of X‐ray diffraction analyses show that the NiII atoms in complexes 1 and 2 are distorted octahedral geometries. Interestingly, the degree of distortion of the ligands in complexes 1 and 2 is different, which indicates that the interaction of NiII ions on different ligands is different. Meanwhile, the investigation of molecular packing by employing the Hirshfeld surface analysis exhibits that the percentages of C–H/H–C, O–H/H–O, and H–H/H–H contacts of the complex 1 (or 2) are calculated to be 17.7%, 7.9%, and 53.7% (or 18.8%, 13.8%, and 52.5%), respectively, where the H–H/H–H contacts have the characteristics of strong contacts whereas the O–H/H–O hydrogen bonds are considerably weak, and the studies on fluorescence properties further confirm the NiII atoms have different binding abilities to the different ligands. [ABSTRACT FROM AUTHOR]

Four new solvent‐induced Ni(II) complexes with chemical formulae [{NiL(μ2‐OAc)(MeOH)}2Ni]·2MeOH (1), [{NiL(μ2‐OAc)}2(n‐PrOH)(H2O)Ni]·n‐PrOH (2), [{NiL(μ2‐OAc)(DMF)}2Ni] (3) and [{NiL(μ2‐OAc)(DMSO)}2Ni]·2DMSO (4), (H2L = 4‐Nitro‐4′‐chloro‐2,2′‐[(1,3‐propylene)dioxybis(nitrilomethylidyne)]diphenol) have been synthesized and characterized by elemental analyses, FT‐IR, UV–Vis spectra and X‐ray crystallography. X‐ray crystal structure determinations revealed that each of the Ni(II) complexes 1–4 consists of three Ni(II) atoms, two completely deprotonated (L)2− units, two μ2‐acetate ions and two coordinated solvent molecules (solvents are methanol, n‐propanol, water, N,N‐dimethylformamide and dimethyl sulphoxide, respectively). Although the four complexes 1–4 were synthesized in different solvents, it is worthwhile that the Ni(II) atoms in the four complexes 1–4 adopt hexa–coordinated with slightly distorted octahedral coordination geometries, and the ratios of the ligand H2L to Ni(II) atoms are all 2: 3. The complexes 1–4 possess self‐assembled infinite 1D, 3D, 1D and 2D supramolecular structures via the intermolecular hydrogen bonds, respectively. In addition, fluorescence behaviors were investigated in the complexes 1–4. [ABSTRACT FROM AUTHOR]

A novel naphthalenediol‐based bis(salamo)‐type tetraoxime compound (H4L) was designed and synthesized. Two new supramolecular complexes, [Cu3(L)(μ‐OAc)2] and [Co3(L)(μ‐OAc)2(MeOH)2]·4CHCl3 were synthesized by the reaction of H4L with Cu(II) acetate dihydrate and Co(II) acetate dihydrate, respectively, and were characterized by elemental analyses and X‐ray crystallography. In the Cu(II) complex, Cu1 and Cu2 atoms located in the N2O2 sites, and are both penta‐coordinated, and Cu3 atom is also penta‐coordinated by five oxygen atoms. All the three Cu(II) atoms have geometries of slightly distorted tetragonal pyramid. In the Co(II) complex, Co1 and Co3 atoms located in the N2O2 sites, and are both penta‐coordinated with geometries of slightly distorted triangular bipyramid and distorted tetragonal pyramid, respectively, while Co2 atom is hexa‐coordinated by six oxygen atoms with a geometry of slightly distorted octahedron. These self‐assembling complexes form different dimensional supramolecular structures through inter‐ and intra‐molecular hydrogen bonds. The coordination bond cleavages of the two complexes have occurred upon the addition of the H+, and have reformed again via the neutralization effect of the OH−. The changes of the two complexes response to the H+/OH− have observed in the UV–Vis and 1H NMR spectra. [ABSTRACT FROM AUTHOR]

A novel dinuclear Zn(II) complex with the chemical formula [Zn2(L)(OCH3)] has been synthesized by a bis(salamo)‐type tetraoxime ligand based on 3‐bromo‐5‐chlorosalicylicaldehyde, and characterized by elemental analyses, IR, UV–vis, and fluorescent spectra, and single‐crystal X‐ray diffraction analysis. All the Zn(II) atoms are pentacoordinated by N2O2 donor atoms from the (L)3− unit and one oxygen atom from one μ2‐methoxyl group. The Zn(II) (Zn1 and Zn4) atoms have distorted square pyramidal geometries (τ1 = 0.458, τ4 = 0.388), whereas the Zn2 and Zn3 atoms adopt trigonal bipyramidal (τ2 = 0.675, τ3 = 0.550) geometries. The Zn(II) complex is self‐assembled by intermolecular CH···O interactions to form an infinite three‐dimensional supramolecular structure. Interestingly, the intermolecular CH···π interactions in the Zn(II) complex is involved not in the formation of three‐dimensional structures but rather in the formation of the 0D dimer structure. Meanwhile, the optical properties of the Zn(II) complex were also measured and are discussed. [ABSTRACT FROM AUTHOR]

A series of homo- and hetero-trinuclear cobalt(II) complexes [Co3(L)(OAc)2(CH3CH2OH)(H2O)] (1), [Co2Ba(L)(OAc)2] (2) and [Co2Ca(L)(OAc)2]·CHCl3 (3), containing an acyclic naphthalenediol-based ligand H4L were synthesized. All the three complexes were characterized by elemental analyses, IR, UV–vis spectra and single crystal X-ray diffraction analyses. Comparative studies of the structures and spectroscopic properties are carried out on these complexes. All of the complexes show catechol oxidase activities in MeCN. Using UV–vis spectroscopy, we monitored the aerial oxidation of 3,5-di-tert-butylcatechol (3,5-DTBCH2) to 3,5-di-tert-butylquinone (3,5-DTBQ), which confirms the essential role of these complexes in enhancing the catalytic reaction. [ABSTRACT FROM AUTHOR]

Plant mating systems rapidly respond to pollen limitation in changing environments. However, whether and how floral traits are involved in a mating system shift requires further investigation. A widely distributed and bumblebee-pollinated lousewort, Pedicularis siphonantha D. Don was studied. We investigated pollination systems, reproductive success, and floral traits in four large populations growing from 3200 m to 4300 m. Pollinator activity in low altitude populations was lower and these populations had a decreased fruit set and seed number per capsule compared to populations at high altitudes. Supplemental hand pollination with outcross pollen significantly increased seed production per capsule for plants from high altitudes but not for those from lower altitudes. We also found that bumblebees visited more flowers within an inflorescence in a single foraging bout in high altitudes compared with low altitudes, which caused a high possibility of geitonogamous mating. These differences may be pollination-dependent rather than inheritance-based because hand pollination on bagged flowers did not cause a difference in seed production across populations. Compared to plants from low altitudes, high-altitude plants had increased flower longevity, larger floral displays, higher pollen production per flower, and shorter corolla tubes, which were found to be well in accordance with changes in both pollination environment and mating system. Plasticity in floral traits might help plants to adjust their resource allocation strategies in response to their habitat, which might be linked with pollination environment. The variability among these populations might be beneficial for this widely distributed species to cope with environmental changes. [ABSTRACT FROM AUTHOR]

Nickel(II) can be used to catalyze the hetero [2+2+1] cycloaddition of 2-alkynylaryl isothiocyanates and isonitriles in 2-methyltetrahydrofuran (2-MeTHF) to give a wide array of thieno[2,3- b]indoles in excellent yields. The reaction is featured by employing as little as 0.3 mol% nickel(II) acetylacetonate [Ni(acac)2] under air conditions in the absence of any additives (additional reducing agents and external ligands). This is the first successful example to apply nickel(II) directly in hetero [2+2+1] cycloadditions. [ABSTRACT FROM AUTHOR]

A new tetranuclear Zn( II) complex, [{Zn(L)(μ- OAc)Zn( H2O)}2], based on an asymmetrical salamo-type bisoxime chelating ligand H3L (6-hydroxy-4′-chloro-2,2′-[ethylenediyldioxybis(nitrilomethylidyne)]diphenol) was synthesized and characterized by elemental analyses, differential thermal methods, single-crystal X-ray crystallography, and IR, UV-vis, and fluorescence spectra. The Zn( II) complex crystallizes in the triclinic system, space group P-1 with cell parameters a = 9.0742(6) Å, b = 11.8225(5) Å, c = 12.4182(8) Å, Z = 2, V = 1212.56(12) Å3, R1 = 0.0572, and wR2 = 0.1734. The environment of the tetranuclear Zn(II) complex is penta-coordinated having a slightly distorted trigonal bipyramidal geometry. Moreover, a 1D chain supramolecular structure is formed along the c-axis by the intermolecular C1-H1B⋯O14 hydrogen bonds; in the same manner, C2-H2C⋯Cg2 functions in the formation of supramolecular structures along the a-axis of the 1D chain. A 2D supramolecular structure along the ac plane extends infinitely under the force of intermolecular hydrogen bonds. Differential scanning calorimetry-thermogravimetry thermal analysis provides evidence of the coordination of Zn(II) atoms to the ligand H3L. The Zn(II) complex shows intense photoluminescence with a maximum emission at ~453 nm upon excitation at 360 nm. [ABSTRACT FROM AUTHOR]

By self-assembly of a Salamo-type ligand H2L [H2L = 1,2-bis(3-methoxysalicylideneaminooxy)ethane] with Ni(OAc)2·4H2O, Ce(NO3)3·6H2O, and H2bdc (H2bdc = terephthalic acid), a novel NiII-CeIII heterometallic complex, [{Ni(L)Ce(NO3)2(CH3OH) (DMF)}2(bdc)], was obtained. Two crystallographically equivalent [Ni(L)Ce(NO3)2(CH3OH)(DMF)] moieties lie in the inversion center, and are linked by one bdc2- ligand leading to a heterotetranuclear dimer, in which the carboxylato group bridges the NiII and CeIII atoms. Moreover, the photophysical properties of the NiII-CeIII complex were studied. [ABSTRACT FROM AUTHOR]

Two trinuclear CoII and ZnII complexes, [(CoL)2(OAc)2Co] and [(ZnL)2(OAc)2Zn], with an asymmetric Salen-type bisoxime ligand [H2L = 4-( N, N-diethylamine)-2,2′-[ethylenediyldioxybis(nitrilomethylidyne)]diphenol] were synthesized and characterized by elemental analyses, IR, UV/Vis, and fluorescent spectroscopy. The crystal structures of the CoII and ZnII complexes were determined by single-crystal X-ray diffraction methods. The CoII atom is pentacoodinated by N2O2 donor atoms from the (L)2- unit and one oxygen atom from the coordinated acetate ion, resulting in a trigonal bipyramid arrangement. With the help of intermolecular hydrogen bonding C-H ···O and C-H ···π interactions, a self-assembled continual zigzag chain-like supramolecular structure is formed. The ZnII atom is pentacoodinated by N2O2 donor atoms from the (L)2- unit and one oxygen atom from the coordinated acetate ion, resulting in an almost regular trigonal bipyramid arrangement. A self-assembled continual 1D supramolecular chain-like structure is formed by intermolecular hydrogen bonding C-H ···O and C-H ···π interactions. Additionally, the photophysical properties of the CoII and ZnII complexes were discussed. [ABSTRACT FROM AUTHOR]

Mononuclear copper(II) and trinuclear cobalt(II) complexes, namely [Cu(L1)]2 ·CH2Cl2 and [{Co(L2)(EtOH)}2Co(H2O)] ·EtOH {H2L1 = 4,6-dichloro-6′-methyoxy-2,2′-[1,1′-(ethylenedioxydinitrilo)dimethylidyne]diphenol and H3L2 = 6-ethyoxy-6′-hydroxy-2,2′-[1,1′-(ethylenedioxydinitrilo)dimethylidyne]diphenol}, were synthesized and characterized by elemental analyses, IR and UV/Vis spectroscopy, and single-crystal X-ray diffraction. In the CuII complex, the CuII atom is four-coordinate, with a N2O2 coordination sphere, and has a slightly distorted square-planar arrangement. Interestingly, the obtained trinuclear CoII complex is different from the common reported 2:3 (L:CoII) salamo-type CoII complexes. Infinite 2D layer supramolecular structures are formed via abundant intermolecular hydrogen bonding and π ···π stacking interactions in the CuII and CoII complexes. [ABSTRACT FROM AUTHOR]

The asymmetric Salamo-type N2O2 ligand H2L and its corresponding CuII and ZnII complexes [CuL] and [{ZnL}2]·2CH3CN were synthesized and structurally characterized. Crystallographic data of the CuII complex revealed that the CuII ion is tetracoordinate with a slightly distorted square planar arrangement forming a 2D supramolecular plane structure by hydrogen bonding and π···π stacking interactions. In the ZnII complex, the ZnII ions are pentacoordinate in N2O2 tetradentate fashion and intermolecular contacts between ZnII and oxygen atoms result in a head-to-tail dimer. The ZnII ions were found to have slightly distorted square pyramidal and trigonal bipyramidal arrangements, respectively. Hydrogen bonding interactions stabilized the ZnII complex to facilitate self-assembly to a 1D linear chain. The CuII and ZnII complexes show intense photoluminescence with maximum emissions at approx. 426 and 411 nm upon excitation at 360 and 350 nm, respectively. [ABSTRACT FROM AUTHOR]

A Salamo-type ligand 6,6′-diethoxy-2,2′-[1,1′-(ethylenedioxydinitrilo)dimethylidyne]diphenol (H2L) and its pentacoordinate copper(II) complex [CuL(H2O)] were synthesized and structurally characterized. The molecule of H2L is located in a crystallographic inversion center and adopts E configuration with respect to the C=N bond. In the complex [CuL(H2O)], the CuII atom has a tetragonally elongated square-pyramidal configuration with donor atoms N2O2 forming a perfect basal plane. And an infinite 2D layer supramolecular structure is formed through intermolecular C1-H1A ···O5 and C2-H2A ···O3 hydrogen bonding interactions. [ABSTRACT FROM AUTHOR]

Two nickel(II) complexes, namely {[NiL(MeOH)(μ-OAc)]2Ni} ·2CH2Cl2 ·2MeOH ( 1) and {[NiL(EtOH)(μ-OAc)]2Ni} ·2EtOH ( 2) {H2L = 5, 5′-dimethoxy-2, 2′-[(ethylene)dioxybis(nitrilomethylidyne)]diphenol}, were synthesized and structurally characterized. Two trinuclear NiII complexes are both hexacoordinate around the central NiII atoms, showing octahedral coordination arrangements, and each complex comprises three divalent NiII atoms, two deprotonated L2- ligands, in which four μ-phenoxo oxygen atoms forming two [NiL( X)] ( X = MeOH or EtOH) units, and coordinated and non-coordinated solvent molecules. Complex 1 exhibits a 2D supramolecular network through intermolecular O-H ···O, C-H ···O and C-H ···π interactions, whereas complex 2 forms an infinite 1D chain by intermolecular C-H ···O hydrogen bonding interactions. [ABSTRACT FROM AUTHOR]

Background: Perioperative fluid restriction can lead to better clinical outcomes and reduced complications. However, whether perioperative fluid restriction can alter the patient's postoperative cellular immunity is unknown. Therefore, a randomized, prospective clinical study was designed to determine whether fluid restriction improves immunological outcome in elderly patients who undergo gastrointestinal surgery for cancer removal. Methods: A total of 179 patients aged 65 years or older were recruited for the study and were randomly assigned to receive the restricted fluid regimen (R group) or the standard fluid regimen (S group). Postoperative T-lymphocyte subpopulations (CD3, CD4, and CD8) frequencies and monocyte HLA-DR expression was investigated. Perioperative complications and cellular immunity changes were analyzed comparatively between the two groups. Results: The restricted intravenous fluid regimen was associated with significantly less postoperative complications (1.5 complications/patient vs. S group: 2.2 complications/patient), especially for infection complications (15% vs. S group: 27%, p = 0.04). Circulating CD3 T-cells were suppressed after surgery in both treatment groups, but the cell frequency (cell/μL) was higher in the R group (746 vs. S group: 480 at postoperative day (POD) 2, p = 0.022; 878 vs. 502 at POD 3, p = 0.005; 892 vs. 674 at POD 5, p = 0.042). Similarly, the HLA-DR expression (% of all T cells) in monocytes were decreased in both groups, but the expression remained higher in the R group (66.20 vs. S group: 51.97 at POD 1, p = 0.029; 68.19 vs. 51.26 at POD 2, p = 0.039; 72.19 vs. 57.45 at POD 3, p = 0.014; 73.92 vs. 60.46 at POD 5, p = 0.036). Multivariate analysis suggested that perioperative CD3 T cell changes were associated with the development of postoperative complications [odds ratio (OR) = 1.963; 95% confidence interval (CI) 1.019-3.782; p = 0.044] and postoperative infections (OR = 3.106; 95% CI 1.302-7.406; p = 0.011). Conclusions: In elderly gastrointestinal cancer patients, cellular immunity is better preserved by the perioperative fluid restriction regimen. The better preserved cellular immunological function is correlated with a reduced perioperative complications rate. [ABSTRACT FROM AUTHOR]

Comprehensive high-performance epoxy nanocomposites were successfully prepared by co-incorporating organo-montmorillonite (o-MMT) and nano-SiO2 into epoxy matrix. Because of the strong interaction between nanoscale particles, the MMT layers were highly exfoliated, and the exfoliated nanoscale MMT monoplatelets took an interlacing arrangement with the nano-SiO2 particles in the epoxy matrix, as evidenced by X-ray diffraction measurement and transmission electron microscopy inspection. Mechanical tests and thermal analyses showed that the resulting epoxy/o-MMT/nano-SiO2 nanocomposites improved substantially over pure epoxy and epoxy/o-MMT nanocomposites in tensile modulus, tensile strength, flexural modulus, flexural strength, notch impact strength, glass transition temperature, and thermal decomposition temperature. This study suggests that co-incorporating two properly selected nanoscale particles into polymer is one pathway to success in preparing comprehensive high-performance polymer nanocomposites. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 [ABSTRACT FROM AUTHOR]

A series of luminescent lanthanide complexes with a new tripodal ligand featuring salicylamide arms, 2,2′,2″-nitrilotris(2-furfurylaminoformylphenoxy)triethylamine (L), were synthesized and characterized by elemental analysis, IR and molar conductivity measurements. Photophysical properties of the complexes were studied by means of UV-vis absorption and steady-state luminescence spectroscopy. Excited-state luminescence lifetimes and quantum yield of the complexes were determined. Luminescence studies demonstrated that the tripodal ligand featuring salicylamide arms exhibits a good antennae effect with respect to the Tb(III) and Dy(III) ion due to efficient intersystem crossing and ligand to metal energy transfer. From a more general perspective, this work offers interesting perspectives for the development of efficient luminescent stains and enlarges the arsenal for developing novel luminescent lanthanide complexes of salicylamide derivatives. Copyright © 2009 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Phylogenetic relationships of the different species in the genus Dendranthema (DC.) Des Moul. were estimated based on chromosome fluorescent in situ hybridization (FISH) with 18S-26S rDNA of Arabidopsis and genomic DNA of Dendranthema as probes. The results revealed that there was no positive correlation between the number of nuclear organization region (NOR) loci and the ploidy of Dendranthema. The exact cytogenetic information of NORs about 14 operational taxonomic units (OTUs) indicated that D. vestitum (Hemsl.) Ling et Shih was closer to the cultivars than other putative species, whereas D. zawadskii (Herb.) Tzvel. was the most distinct. The ambiguously distributed signals of genomic in situ hybridization (GISH) with genomic DNA of lower ploidy species as probes suggested that different genomes among Dendranthema were mixed. The result also indicated the limitation of GISH in studies on the phylogenetic relationships of the different species in this genus Dendranthema and on the origin of cultivated chrysanthemums. Based on these results and previous research, the origin of Chinese cultivated chrysanthemum is discussed. (Managing editor: Wei WANG) [ABSTRACT FROM AUTHOR]

ABSTRACT A novel salamo‐Co (II) coordination polymer probe CP was synthesized firstly, and its crystal structure, [Co3(L)2(PTA)(H2O)2]n·4nDMF, was determined by X‐ray diffraction analysis. The probe has a rare aggregation‐induced luminescence enhancement (AIEE) effect. When applied to amino acid detection, it was found to have a high selective recognition of tyrosine. With the increase of tyrosine, the fluorescent strength of the probe was enhanced in a short period of time. In addition, the binding ratio of probe to Tyr was determined by fluorescence titration experiment, and the detection limit LOD of probe CP for Tyr was calculated to be 2.57 × 10−9 M, and the binding constant Ka was 2.96 × 105 M−1. According to UV absorption spectrum, FT‐IR spectra, ESI mass spectrometry, and DFT calculation, it was speculated that Tyr can bind to the probe after adding Tyr into the probe solution, triggering FRET and ICT effects, resulting in increased fluorescence intensity and blue shift, and finally achieving the specific recognition of tyrosine by probe CP. Finally, the practical application of probe CP was studied. Through strip test and real water sample test, it was found that the probe can be used for qualitative and quantitative analysis of tyrosine. [ABSTRACT FROM AUTHOR]

ABSTRACT A mono‐salamo‐type ligand H2L was prepared to utilize 3‐methoxysalicylaldehyde and a semi‐salamo‐type compound, and its novel trinuclear Ni(II) cluster with two significantly various configurations in the solid state was obtained by reaction of H2L with Ni(II) ions. The trinuclear structure of the Ni(II) cluster was validated by x‐ray technique, and Ni(II) ions exhibited hexa‐coordinated twisted octahedrons. Its structural formula is [Ni3(L)2(μ2‐Cl)2(EtOH)2]. Chloride ions have also successfully double bridged to participate in coordination, and play a critical impact in the trinuclear configuration's stability and charge balance. Two solvent ethanol molecules are also participated in coordination. The coordination ratio of the ligand to the metal ion was verified to be 2:3 by UV–Vis absorption titration spectroscopy. The HOMO and LUMO energies of the frontline molecular orbitals of H2L and the complex were analyzed by DFT calculations, and the energy gap value of the ligand H2L was 4.29 eV, and that of the complex was 0.72 eV. The ligand combined with the metal decreased the energy gap value and produced a more active complex. Furthermore, Hirshfeld surface analysis visualizes the weak interactions of crystalline molecules, and these abundant weak interactions play an especially critical effect in the supramolecular structural self‐assembling. The fluorescent researches proclaimed that the fluorescence intensity of the cluster significantly decreased compared with the ligand, suggesting that this ligand and complex have greater promise for fluorescence sensing. [ABSTRACT FROM AUTHOR]

Inherently chiral calixarenes have garnered significant attention due to their distinctive properties, yet the development of efficient catalytic asymmetric synthesis methods remains a critical challenge. Herein, we report the asymmetric synthesis of calix[4]arenes featuring inherent or both inherent and axial chirality via a cobalt‐catalyzed C−H activation/annulation strategy in high yield with excellent enantio‐ and diastereoselectivity (up to >99 % ee and >20 : 1 dr). Electrooxidation was also suitable for this transformation to obviate the sacrificial metal oxidants, underscoring the environmentally friendly potential of this approach. A key octahedral cobaltacycle intermediate was synthesized and characterized, providing valuable insights into the mode of enantio‐ and diastereocontrol of this protocol. Noteworthy photoluminescence quantum yields of up to 0.94 were measured, underscoring the potential of these compounds in the domain of organic fluorescent materials. [ABSTRACT FROM AUTHOR]

Two hetero‐bimetallic [Zn(II)2M(II)] (M = Ca and Sr) complexes [Zn2Ca(L)(OAc)2] (1) and [Zn2Sr(L)(OAc)2] (2) with a novel asymmetrical bis(salamo)‐type tetraoxime ligand (H5L) were designed and synthesized, and characterized by elemental analyses, FT‐IR spectra, UV–vis absorption spectra, Density Functional Theory (DFT) calculation, Hirshfeld surface analyses and X‐ray single crystal diffractions. Compared with the symmetric bis(salamo)‐type ligands, the ligand H5L and its [Zn(II)2M(II)] (M = Ca and Sr) asymmetrical bis(salamo)‐type complexes synthesized for the first time in this paper have more novel structures and better properties. The results of ultraviolet titration show that the coordination ratio of ligand, alkaline earth metal and transition metal is 1:1:2. Complexes 1 and 2 have good luminescent properties and obvious antimicrobial activities. [ABSTRACT FROM AUTHOR]

Three multinuclear Cu (II), Zn (II) and Cd (II) complexes, [Cu2(L)(μ‐OAc)]·CHCl2 (1), [Zn2(L)(μ‐OAc)(H2O)]·3CHCl3 (2) and [{Cd2(L)(OAc)(CH3CH2OH)}2]·2CH3CH2OH (3) with a single‐armed salamo‐like dioxime ligand H3L have been synthesized, and characterized by FT‐IR, UV–vis, X‐ray crystallography and Hirshfeld surfaces analyses. The ligand H3L has a linear structure and C‐H···π interactions between the two molecules. The complex 1 is a dinuclear Cu (II) complex, Cu1 and Cu2 are all five‐coordinate possessing distorted square pyramidal geometries. The complex 2 also forms a dinuclear Zn (II) structure, and Zn1 and Zn2 are all five‐coordinate bearing distorted trigonal bipyramidal geometries. The complex 3 is a symmetrical tetranuclear Cd (II) complex, and Cd1 is a hexa‐coordinate having octahedral configuration and Cd2 is hepta‐coordinate with a pentagonal bipyramidal geometry, and it has π···π interactions inside the molecule. In addition, fluorescence properties of the ligand and its complexes 1–3 have also been discussed. [ABSTRACT FROM AUTHOR]

Three newly designed containing‐PMBP N2O2‐donors complexes, [Co(L1)(CH3OH)2] (1), [{Zn(L2)(CH3OH)(H2O)}3] (2) and [Cu4(L2)4]⋅2CHCl3 (3), have been synthesized and structurally characterized using elemental analyses, infrared and UV–visible spectroscopies and single‐crystal X‐ray diffraction. X‐ray crystal structure determinations revealed that 1 consists of one Co(II) atom, one completely deprotonated (L1)2− unit and two coordinated methanol molecules. Complex 2 consists of three Zn(II) atoms, three completely deprotonated (L2)2− units, three coordinated methanol molecules and three coordinated water molecules. However, 3 includes four Cu(II) atoms, four completely deprotonated (L2)2− units and two crystallization chloroform molecules. The Co(II) and Zn(II) atoms in the structures of 1 and 2 adopt slightly distorted octahedral geometries. While, Cu(II) atoms in 3 can be best described as adopting slightly distorted square planar geometries. Complex 2 is a novel structure, and the ratio of H2L2 to Zn(II) atom is 3:3. In addition, two‐, three‐ and three‐dimensional supramolecular structures were constructed for 1, 2 and 3. Most importantly, Hirshfeld surface analysis of 1, 2 and 3 was conducted and fluorescence properties were investigated. [ABSTRACT FROM AUTHOR]

Rare homo‐ and hetero‐polynuclear transition metal(II) complexes, [{Cu(L1)}2] (1) and [Cu(L2)Ni2(CH3OH)2] (2), were prepared and structurally characterized. Complex 1 possesses an uncommon dinuclear structure bonded by two alkoxy bridges, and all the Cu(II) atoms are tetra‐coordinated with slightly distorted square planar geometries. The Cu1─Cu2 bond distance is 2.994(3) Å. Complex 2 exhibits an unexpected trinuclear heterobimetallic structure from two chelating (L2)3− units in crossover mode, which is the first heterobimetallic 3d–3d salamo‐type transition metal complex. The two Ni(II) atoms are penta‐coordinated with slightly distorted square pyramidal geometries (τ = 0.269 (Ni1) and 0.498 (Ni2)), and the Cu(II) atom is tetra‐coordinated with a slightly distorted square planar geometry. Moreover, fluorescence behaviors of 1 and 2 were investigated, and electrochemical study reveals that the electrolytic redox reactions of 1 are irreversible processes. Rare homo‐ and hetero‐polynuclear transition metal(II) complexes, [{Cu(L1)}2] (1) and [Cu(L2)Ni2(CH3OH)2] (2), were prepared and characterized. Complex 1 possesses an uncommon dinuclear structure bonded by two alkoxy bridges. Complex 2 exhibits an unexpected trinuclear heterobimetallic structure from two chelating (L2)3− units in crossover mode. Fluorescence behaviors of 1 and 2 were investigated, and electrochemical experiments revealed that electrolytic redox reactions of 1 are irreversible processes. [ABSTRACT FROM AUTHOR]

The mild and efficient procedure affords a series of pharmaceutically interesting title heterocycles bearing a broad spectrum of functionalities and a (Z) configurated side chain. [ABSTRACT FROM AUTHOR]

The title compound, C16H14Br2N2O4, has been synthesized by the reaction of 1,2-bis­(amino­oxy)ethane with 5-bromo-2-hydroxy­benzaldehyde in ethanol. The molecule is centrosymmetric. Intra­molecular O—H⋯N hydrogen bonding is observed between hydr­oxy groups and oxime N atoms. [ABSTRACT FROM AUTHOR]

The mol­ecule of the title compound, C13H11N3OS, is non-planar; the dihedral angles between the thio­urea and pyridine planes and between the thio­urea and benzene planes are 41.28 (8) and 27.47 (8)°, respectively. [ABSTRACT FROM AUTHOR]