Structure and luminescent property of a Sm3+ complex containing benzoyltrifluoroacetone and 1,2-bis[(anthracen-9-ylmethyl)amino]ethane ligands

The synthesis, structure, and luminescent propertiesof a samarium(III) complex (A2) containing benzoyltrifluoroacetone (HTFPB) and 1,2-bis[(anthracen-9-ylmethyl)amino]ethane (BAAE2) ligands are herein reported. The structure of A2 has been elucidated by infrared spectroscopy and single crystal X-ray diffraction. X-ray crystallographic analysis demonstrated that A2 has a mononuclear structure with a formula of Sm(TFPB)3(BAAE2) in which Sm3+ ion is coordinated to six O-atoms from three TFPB ligands and two N-atoms from one ancillary ligand (BAAE2). UV-Vis data show that A2 strongly absorbs in the region of 220-400 nm. Nonetheless, A2 gives poor emission due to a quenching effect of the anthracenyl moiety.

Pd(II) and Zn(II) Complexes with 9-Anthraldehyde 3-tetramethyleneiminylthiosemicarbazone

Two Pd(II) and Zn(II) complexes with an anthracene-based thiosemicarbazone (H-5cATSC) have been conveniently prepared. Reaction of the ligand with relevant metal precusors yields the complexes Pd-5cATSC and Zn-5cATSC which have been then structurally determined by X-ray crystallography. The results reveals that the complexes are of mononuclear structure and adopts square-planar and tetrahedral geometries around the central metal ions.

Synthesis, structural characterization, and properties of Co(II) and Zn(II) complexes with a mixed N- and O-donor ligand

The hydrothermal reaction of Co(II) nitrate with 5-(pyridin-4-yl)isophthalic acid (H2L) yields a new complex [Co(L)(H2O)5] · 4(H2O) (1). When 4,4′-bipyridine (bpy) as auxiliary ligand and Zn(II) nitrate were used in the same reaction system, [Zn(L)(bpy)] · 0.5(DMF) · 0.5(H2O) (2) could be obtained. Complexes 1 and 2 have been characterized by single-crystal X-ray diffraction, infrared spectroscopy, and elemental and thermogravimetric analyses. Complex 1 displays a discrete mononuclear structure, whereas 2 exhibits a binodal (3,5)-connected twofold interpenetrated three-dimensional hms framework architecture with (63)(69,8) topology. The fluorescence properties of 2 were also investigated.

Synthesis, structural characterization, and properties of Ag(I) complexes with N-donor ligands

New silver complex [Ag(pz)(CF3SO3)] (1) was formed by the coordination reaction of AgCF3SO3with pyrazine (pz) in the presence of 2-[(S)-4-isopropyl-2-oxazolyl] quinoline (L). When AgBF4was used instead of AgCF3SO3as the starting material, complex2[Ag(L)(CH3CN)](BF4) was obtained. Complexes1and2are characterized by single-crystal X-ray diffraction, IR spectroscopy and elemental, and thermogravimetric analysis. Complex1shows a 3D framework structure with uni-nodal eight-connected (424.64) topology while complex2displays a discrete mononuclear structure. The nonlinear optical properties of2were investigated.

Crystal Structure and Magnetic Property of Novel Ln(III)-Nitronyl Nitroxide Radical Complex

Four novel rare-earth complexes based on a new nitronyl nitroxide radical have been synthesized and characterized as: {[Ln (hfac)3(NITPhBrF)2]·0.5CH2Cl2}(Ln = Sm (1), Gd (2), Tb (3)), {[Ln (hfac)3(NITPhBrF)2]}(Ln = Dy (4)) (hfac = hexafiuoroacetylacetonate; NITPhBrF = 2-(2-fluoro-5-bromophenyl)-tetramethylimidazoline-1-oxyl-3-oxide). The single-crystal X-ray diffraction revealed that compound 1, 2 and 3 are isostructural, which crystallize in the monoclinic space group P21/n, and compound 4 is in the P-1 triclinic space group. These complexes possess mononuclear structure in which the central Ln (III) is octacoordinated by six oxygen atoms from three bidentate hfac ligands and two oxygen atoms from two NITPhBrF ligands. DC magnetic susceptibilities were measured under 1kOe in the 2 - 300 K range. The studies reveal that there exit ferromagnetic interaction between the Gd (III) and radical ligands, and the antiferromagnetic interaction between the two intramolecular radicals in Gd (2). Meanwhile complexes Tb (3) and Dy (4) exhibit antiferromagnetic interactions.

Hybrid 1,2,3-Triazole Supported CuII Complexes: Tuning Assembly and Weak Interaction-Driven Crystal Growth

Two new dinuclear CuII complexes [Cu2Cl4(L1)2] (1) and [Cu2Cl4(L2)2] (2) (L1 = 2-((4-(2-(cyclopentylthio)ethyl)-1H-1,2,3-triazol-1-yl)methyl)pyridine; L2 = 2-((4-(pyridin-2-yl)-1H-1,2,3-triazol-1-yl)methyl)benzonitrile) were synthesised and characterised by single-crystal X-ray diffraction (XRD), powder XRD, thermogravimetric analysis, elemental analysis and IR measurements. The picolyl-triazole ligand L1 coordinates in a chelate-bridging mode forming a dinuclear structure 1. The more rigid pyridyl-triazole ligand L2 chelates only, generating a chloride-bridged dinuclear complex 2. Both crystals of complexes 1 and 2 show dominant plate shapes that correlate with weak 2D H-bonding interactions in the lattice. A mononuclear structure (3, [CuCl2(L3)2]⋅6H2O, L3 = 3-((4-(pyridin-2-yl)-1H-1,2,3-triazol-1-yl)methyl)benzonitrile) yields block shape crystals that correlate with 3D H-bonding interactions. This study demonstrates tunable assembly at the molecular level and the relationship of crystal shape with weak lattice interactions.

Mononuclear and three-dimensional metal complexes based on a multidentate hydrazone ligand

A potentially pentadentate hydrazone ligand,N′-[1-(pyrazin-2-yl)ethylidene]nicotinohydrazide (HL), was prepared from the condensation reaction of nicotinohydrazide and acetylpyrazine. Reactions of HLwith MnCl2, Mn(CH3COO)2and Cd(CH3COO)2afforded three metal complexes, namely dichlorido{N′-[1-(pyrazin-2-yl-κN1)ethylidene]nicotinohydrazide-κ2N′,O}manganese(II), [MnCl2(C12H11N5O)], (I), bis{N′-[1-(pyrazin-2-yl-κN1)ethylidene]nicotinohydrazidato-κ2N′,O]manganese(II), [Mn(C12H10N5O)2], (II), and poly[[(acetato-κ2O,O′){μ3-N′-[1-(pyrazin-2-yl-κ2N1:N4)ethylidene]nicotinohydrazidato-κ3N′,O:N1}cadmium(II)] chloroform disolvate], {[Cd(C12H10N5O)(CH3COO)]·2CHCl3}n, (III), respectively. Complex (I) has a mononuclear structure, the MnIIcentre adopting a distorted square-pyramidal coordination. Complex (II) also has a mononuclear structure, with the MnIIcentre occupying a special position (C2symmetry) and adopting a distorted octahedral coordination environment, which is defined by two O atoms and four N atoms from twoN′-[1-(pyrazin-2-yl)ethylidene]nicotinohydrazidate (L−) ligands relatedviaa crystallographic twofold axis. Complex (III) features a unique three-dimensional network with rectangular channels, and theL−ligand also serves as a counter-anion. The coordination geometry of the CdIIcentre is pentagonal bipyramidal. This study demonstrates that HL, which can act as either a neutral or a mono-anionic ligand, is useful in the construction of interesting metal–organic compounds.

Two ZnIIcoordination complexes assembled by trithiocyanuric acid and two different N-donor auxiliary ligands

The dipyridyl-type building blocks 4-amino-3,5-bis(pyridin-3-yl)-1,2,4-triazole (3-bpt) and 4,4′-bipyridine (bpy) have been used to assemble with ZnIIin the presence of trithiocyanuric acid (ttcH3) to afford two coordination compounds, namely bis[4-amino-3,5-bis(pyridin-3-yl)-1,2,4-triazole-κN3]bis(trithiocyanurato-κ2N,S)zinc(II), [Zn(C3H2N3S3)2(C12H10N6)2]·2H2O, (1), andcatena-poly[[[bis(trithiocyanurato-κ2N,S)zinc(II)]-μ-4,4′-bipyridine-κ2N:N′] 4,4′-bipyridine monosolvate], {[Zn2(C3H2N3S3)4(C10H8N2)3]·C10H8N2}n, (2). Single-crystal X-ray analysis indicates that complex (1) is a mononuclear structure, while complex (2) presents a one-dimensional chain coordination motif. In both complexes, the central ZnIIcation adopts an octahedral geometry, coordinated by four N- and two S-donor atoms. Notably, trithiocyanurate (ttcH2−) adopts the same bidentate chelating coordination mode in each complex and exists in the thione tautomeric form. The 3-bpt co-ligand in (1) adopts a monodentate coordination mode and serves as a terminal pendant ligand, whereas the 4,4′-bipyridine (bpy) ligand in (2) adopts a bidentate–bridging coordination mode. The different coordination characters of the different N-donor auxiliary ligands lead to structural diversity for complexes (1) and (2). Further analysis indicates that the resultant three-dimensional supramolecular networks for (1) and (2) arise through intermolecular N—H...S and N—H...N hydrogen bonds. Both complexes have been further characterized by FT–IR spectroscopy and elemental analyses.

Syntheses, Crystal Structures, and Properties of Six Coordination Complexes Based on a Newly Designed Mercapto-thiadiazole Ligand

Six coordination complexes were solvothermally synthesised: a 3D framework [Cd(tmtt)2]n (1), 2D architectures [Zn(tmtt)2]n (2) and [Pb(tmtt)2]n (3), 1D chain structures [Ni(tmtt)2·(H2O)2]n (4) and [Co(tmtt)2·(H2O)2]n (5), and a mononuclear structure [Hg(tmtt)2] (6). The complexes, based on self-assembly of different metal ions with a newly designed mercapto-thiadiazole ligand tmttH (tmttH = 5-[(1H-1,2,4-triazol-1-yl)methyl]-1,3,4-thiadiazole-2(3H)-thione), were characterised by single crystal X-ray diffraction analyses. Crystal structure analyses reveal that complex 1 exhibits a four-fold interpenetrating 3D framework with {64.82} topology based on two kinds of right-handed single-helical chains, 2 displays a bilayer structure, 3 presents a crown-shaped network, 4 and 5 show 1D double–helical chain structures, and 6 is a mononuclear structure. Moreover, the thermal stabilities of crystalline samples 1–6 have been investigated, and the luminescent properties of complexes 1, 2, 3, 6, and the free ligand have been studied. The results of photoluminescent measurements illustrate that 2 and 3 may serve as excellent candidates for potential photoactive materials.

Aquabis(4-nitrobenzoato)-κ2O,O′;κO-(piperidinium-4-carboxylato-κ2O,O′)cadmium(II)

In the mixed ligand title compound, [Cd(C6H11NO2)(C7H4NO4)2(H2O)], which exhibits a discrete mononuclear structure, the CdIIatom is in a distorted octahedral geometry, surrounded by five carboxylate O atoms and one coordinated water molecule. The piperdinium ring adopts a chair conformation and the two 4-nitrobenzoate rings are oriented at a dihedral angle of 75.8 (1)°. Intermolecular O—H...O and N—H...O hydrogen bonds link the mononuclear entities into a three-dimensional supramolecular network.