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A Pd-tBuONO co-catalyzed scalable and practical synthesis of indoles with molecular oxygen as terminal oxidant is developed. Either terminal or internal 2-vinylanilines could be smoothly converted to desired indoles under one general condition. This method has been evaluated in the large scale synthesis of indomethacin and a potential anti-breast cancer drug candidate 1. [ABSTRACT FROM AUTHOR]

A μ-oxido-bridged dinuclear iron(III) complex, [Fe2O(L1)2(L2)2], where L1and L2are the deprotonated forms of 2,4-dichloro-6-[(2-morpholin-4-ylethylimino)methyl]phenol and 3,5-dichlorosalicylaldehyde, respectively, has been prepared and characterized by elemental analysis, infrared spectrum, and single-crystal X-ray determination. The complex crystallizes in the triclinic space groupP, with unit cell dimensionsa= 10.670(1) Å,b= 11.585(1) Å,c= 19.748(2) Å, α = 86.766(2)°, β = 85.038(2)°, γ = 73.973(2)°,V= 2336.1(4) Å3,Z= 2, GOOF = 1.019,R1= 0.0422, andwR2= 0.1024. Structural analysis shows that the iron atoms in the complex are hexacoordinate with a normal Fe-O-Fe bridging angle of 150.84(13)°. Each Fe atom is coordinated by the NNO donor atoms of L1, OO donor atoms of L2, and one bridging O atom. The Fe· · ·Fe distance is 3.467(2) Å. [ABSTRACT FROM PUBLISHER]

Two new mononuclear Schiff base nickel(II) complexes, [Ni(ClSal)] (1) and [Ni(MeSal)] (2) (H2ClSal =N,N′-bis(3,5-dichlorosalicylidene)-1,3-pentanediamine; H2MeSal =N,N′-bis(3-methylsalicylidene)-1,2-ethanediamine), have been synthesized and characterized by elemental analyses, infrared spectra, and single-crystal X-ray diffraction. Complex 1 crystallizes in the orthorhombic space groupP212121, with unit cell dimensionsa= 9.788(1) Å,b= 10.206(1) Å,c= 20.458(2) Å,V= 2043.7(4) Å3,Z= 4,R1= 0.0814, andwR2= 0.1689. Complex 2 crystallizes in the monoclinic space groupP21/n, with unit cell dimensionsa= 11.6353(5) Å,b= 11.8807(6) Å,c= 12.8241(6) Å,β= 115.213(1)°,V= 1603.9(1) Å3,Z= 4,R1= 0.0243, andwR2= 0.0675. The Ni atoms in the complexes are four-coordinated in square planar geometry by the N2O2donor set of the ligands. [ABSTRACT FROM AUTHOR]

A pair of mononuclear Schiff base zinc(II) complexes, [ZnLCl2] (1) and [ZnLBr2] (2), have been prepared by the reaction of equimolar quantities of a new Schiff base ligand 2-[(2-dimethylammonioethylimino)methyl]-4-methylphenolate with ZnCl2and ZnBr2, respectively, in methanol. The structures of the complexes have been characterized by single-crystal X-ray diffraction. Complex 1 crystallizes as orthorhombic space groupP212121, with unit cell dimensionsa= 7.518(1) Å,b= 13.518(2) Å,c= 14.766(2) Å, V = 1500.7(3) Å3, Z = 4,R1= 0.0301,wR2= 0.0780, S = 1.028. Complex 2 crystallizes as orthorhombic space groupP212121, with unit cell dimensionsa= 7.731(1) Å,b= 13.761(1) Å,c= 14.705(1) Å, V = 1564.4(1) Å3, Z = 4,R1= 0.0230,wR2= 0.0488, S = 1.031. The Zn atom in each of the complexes is four-coordinated in a tetrahedral geometry by the phenolate O and imine N atoms of the Schiff base ligand, and two halide anions. Single crystals of the complexes are stabilized by hydrogen bonds. [ABSTRACT FROM AUTHOR]

Three Cu(II) complexes, [CuII2(L1)4(L2)2] (1), [CuII2(L1)4(H2O)2]·HL (2), and [CuII2(L1)3(L3)2]ClO4(3), with a ligand derived from protocatechuic acid (HL1 = C9H8O4=2,3-dihydrobenzo[b][1,4]dioxine-6-carboxylic acid, L2 = C7H9N=o-toluidine, L3 = C6H16N2=N,N-diethylethylenediamine) were synthesized and characterized by C, H, and N elemental analysis and single-crystal X-ray diffraction, which revealed that the three complexes have similar binuclear structures. Complexes1and3crystallized in triclinic space groupP-1and2in orthorhombic space groupP212121. The urease inhibitory activities of the three complexes were tested. All three complexes showed strong inhibitory activity againstjack beanurease with an IC50value of 6.8, 5.5, and 3.5 μM compared with the acetohydroxamic acid (IC50 = 7.5 μM), which was a positive control. [ABSTRACT FROM AUTHOR]

Reaction of [MoO2(acac)2] (where acac = acetylacetonate) with two similar hydrazone ligands in ethanol yielded two ethanol-coordinated mononuclear molybdenum(VI) oxo complexes with general formula [MoO2L(EtOH)], where L = L¹ = (N'-(3,5-dibromo-2-hydroxybenzylidene)-4-nitrobenzohydrazide (H2L¹), and L = L² = (N'-(3,5-dibromo-2- hydroxybenzylidene)-2-fluorobenzohydrazide (H2L²). Crystal and molecular structures of the complexes were determined by single crystal X-ray diffraction method. All of the investigated compounds were further characterized by elemental analysis and FT-IR spectra. Single crystal X-ray structural studies indicate that the hydrazone ligands coordinate to the MoO2 cores through enolate oxygen, phenolate oxygen and azomethine nitrogen. The Mo atoms in both complexes are in octahedral coordination. Thermal stability of the complexes has also been studied. [ABSTRACT FROM AUTHOR]

A new mononuclear Schiff base cobalt(III) complex, [Co(MEA) (N3)(DMF)] (1), and a new mononuclear Schiff base manganese(III) complex, [Mn(EEA)(N3)(OH2)] (2) (MEA is bis (5-methoxysalicylidene)ethylenediamine; EEA is bis(6-ethoxys alicylidene)ethylenediamine), have been prepared and structurally characterized by physicochemical and single-cyrstal X-ray diffraction. Complex 1 crystallizes in the monoclinic space groupP21/cwith unit cell dimensionsa= 9.910(1) Å,b= 19.279(1) Å,c= 12.410(1) Å,β= 102.729(2)°, V = 2312.8(2) Å3, Z = 4,R1= 0.0319, andwR2= 0.0779. Complex 2 crystallizes in the monoclinic space groupP21/cwith unit cell dimensionsa= 14.252(2) Å,b= 22.227(3) Å,c= 13.613(2) Å,β= 91.512(2)°, V = 4310.7(11) Å3, Z = 8,R1= 0.0392, andwR2= 0.0839. The metal atom in each complex is in an octahedral coordination. Crystal of complex 2 was stabilized by hydrogen bonds. [ABSTRACT FROM PUBLISHER]

Six d 10 complexes, [Zn1.5(stp)(bpy)0.5(H2O)2]·0.5H2O (1), Cd1.5(stp)(bpy)0.5(H2O)2 (2), [Cd1.5(stp)(bpy)(H2O)]·H2O (3), [Zn0.5(bpy)0.5(H2O)2][Zn(stp)(bpy)(H2O)]·0.5H2O (4), Cd3(stp)2(bpy)3(H2O)3 (5), Hbpy·[Zn0.5(bpy)(H2O)2][Zn0.5(stp)(H2O)]·H2O (6) based on 2-sulfoterephthalate (stp3−) and 4,4′-bipyridine (bpy) have been synthesized under hydro/solvo-thermal conditions and structurally characterized. Complex 1 exhibits a three-fold interpenetrated 3D porous architecture. Complexes 2 and 3 possess helices with different chirality arranging alternately. 4 and 6 are addition compounds, which compose of complex cation and complex anion. Complex 5 features a 3D layer-pillar framework in which a (4, 4) grid layer is constructed by stp3− ligands and Cd(II) ions, and the layers are further connected by bpy pillars. The solid-state luminescent properties of the coordination polymers have also been investigated. [ABSTRACT FROM AUTHOR]

Five new metal–organic frameworks (MOFs), named [Zn 2 (aobtc)(H 2 O) 4 ] ( 1 ), [Mn 3 (Haobtc) 2 (DMA) 2 (H 2 O) 2 ]·2H 2 O ( 2 ), [Co 3 (Haobtc) 2 (H 2 O) 4 ]·11H 2 O ( 3 ), [Co 3 (aobtc) 2 ]·Himi·H 3 O·3H 2 O ( 4 ), [Cd 2 (aobtc)(bpy)]·4.5H 2 O ( 5 ) (H 4 aobtc = 3,3′,5,5′-azoxybenzenetetracarboxylic acid, bpy = 4,4′-bipyridine, imi = imidazole), have been designed and syntheses. Their structures were determined by single-crystal X-ray diffraction analyses and further characterized by elemental analyses, IR spectra and TG analyses. The five compounds exhibit diverse secondary building units (SBUs) and show various structures with different porosity. Compound 1 is a two-dimensional (2D) layer with (4,4)- sql topology based on binuclear Zn cluster (SBU). Both compounds 2 and 3 possess 2D framework with (3,6)-connected kgd topology, based on trinuclear Mn and Co clusters, respectively. Compound 4 shows a 3D framework with (3,8)-connected flu topology, containing linear trinuclear Co clusters as 8-connected nodes. The 3D framework of Compound 5 is built from infinite Cd–O–Cd rod SBUs. The effects of stacking modes on the crystal architectures are discussed. The solid-state photoluminescence for 1 and 5 , the magnetic properties for 2 – 4 , and CO 2 adsorption for 3 were also investigated. [ABSTRACT FROM AUTHOR]

Abstract: The first example of a novel acetylhydroxamate-coordinated oxovanadium(V) complex with hydrazone ligand has been prepared and structurally characterized. The urease inhibitory activity of the complex was assayed, and the molecular docking study was performed. The complex has strong urease inhibitory activity. The introduction of acetylhydroxamate ligand as functional urease inhibitory group may increase the activity of the complex. [Copyright &y& Elsevier]

Abstract: The α-MoO3/graphene composites (MoO3/G) were prepared via an in situ hydrothermal synthesis. The composites were characterized using various characterization techniques including powder X-ray diffraction, transmission electron microscopy, scanning electron microscopy, X-ray photoelectron spectroscopy, and the electrochemical performance test. The results show that these MoO3/G composites exhibit high capacity and good cycle stability when used as the lithium-ion battery anode. Among all the samples, the MoO3/G-27 reveals the best electrochemical performance with an initial charge capacity of 977.7 mAh g−1 at a current density of 50 mA g−1, the first coulombic efficiency of 69.5%. After eighty cycles the electrode still maintains a capacity of 869.2 mAh g−1, giving high capacity retention of 88.9%. The good electrochemical performance of the composite anode is close related to its structure, in which the MoO3 nanobelts are not only homogeneously anchored on the surface but also embedded in the interlayer of the graphene sheets; hence the volume change and aggregation of the MoO3 nanobelts during lithium ion insertion/extraction process can be effectively hindered. On the other hand, graphene itself is an electronic conductor; the graphene and MoO3 nanobelts connect closely, which offers large electrode/electrolyte contacting area, short path length for Li+ transporting during lithium insertion and extraction. [Copyright &y& Elsevier]

Abstract: A series of 2,5-substituted-1,4-benzoquinone (1–6) were prepared and structurally characterized by elemental analysis, IR spectra, 1H and 13C NMR spectra, and single crystal X-ray determination. The urease inhibitory activities of the compounds against H. pylori urease were studied. Among the compounds, 2,5-bis(2-morpholin-4-ylethylamino)-[1,4]benzoquinone (2) shows the most effective activity with IC50 value of 27.30±2.17μM. Docking simulation was performed to insert compound 2 into the crystal structure of H. pylori urease at the active site to determine the probable binding mode. As a result, compound 2 may be used as a potential urease inhibitor. [Copyright &y& Elsevier]