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This paper describes the synthesis and structural characterization of two new one-dimensional coordination polymers involving 1,3-bis(4-pyridyl)propane ligand named {(μ-NCS)2[Cu(bpp)] ·dmf} n ( 1) and {[Cu(mebpy)(bpp)(dmso)](ClO4)2 ·dmso} n ( 2) (bpp = 1,3-bis(4-pyridyl)propane and mebpy = 4,4'-dimethyl-2,2'-bipyridine). These compounds were characterized by means of elemental analysis, thermal analysis (TG/DTA), vibrational spectroscopy (IR and Raman) and had their structures determined by single-crystal X-ray diffraction analysis. Compound 1 consists of CuN4 coordination spheres with bpp ligands in the unusual GG conformation coordinated in bridges between CuII centers to form a wavelike 1-D coordination polymer. On the other hand, in compound 2 the bpp ligand adopts the TT conformation in bridging mode extending the 1D cationic polymeric chain. [ABSTRACT FROM AUTHOR]

The reaction of Co(CO)4H with various 1,1'-bis(diorganophosphanyl) ferrocenes (dopf) produces structurally different heterodinuclear (Co,Fe) compounds. In contrast to the P-isopropyl and P-cyclohexyl- substituted complexes [Co(CO)2H(dopf)] described earlier, the P-phenyl-substituted analogue exhibits a structure in the crystal with the hydride in trans position to a P atom. Using the dopf precursor with bulky P-tert-butyl substituents, a heterotrinuclear species {(μ- dtbpf)[Co(CO)3H]2} is obtained, in which the ferrocene-containing ligand acts as a bridge. In addition to the comparative analysis of molecular structures the (spectro)electrochemical responses are discussed in the light of the mechanism established for the isopropyl-substituted system. [ABSTRACT FROM AUTHOR]

Recently, Brønsted acids, such as phosphoric acids, carboxylic acids, and triflic acid, were found to catalyze the reduction of phosphine oxides to the corresponding phosphines. In this study, we fully characterize the HCl, HOTf, and Me2SiHOTf adducts of triphenylphosphine oxide and find that the thermally stable adduct Ph3POH+Otf- is efficiently converted into triphenylphosphine at 100 °C in the presence of readily available hydrosiloxanes. Under the same reaction conditions, also Ph3POSiMe2H+Otf- selectively affords triphenylphosphine indicating that silylated phosphine oxides are likely intermediates in this process. [ABSTRACT FROM AUTHOR]

Energetic copper(II) complexes based on 3,5-dinitrobenzoic acid (HDNBA) and 1,5-diaminotetrazole (DAT), Cu(DNBA)2(H2O)2 ( 1) and Cu(DAT)2(DNBA)2 ( 2) were synthesized and characterized by elemental analysis, IR spectroscopy, single-crystal and powder X-ray diffraction. In both complexes, CuII was coordinated to a plane tetragon, by four oxygen atoms from two DNBA- ions and two coordinated H2O molecules for 1, and by two oxygen atoms and two nitrogen atoms from different DNBA- ions and DAT ligands for 2. Differential scanning calorimetry (DSC) and thermogravimetry (TG) analyses were employed to measure the thermal decomposition processes and non-isothermal kinetics parameters of the complexes. The thermal decomposition onset temperatures of 1 and 2 are 321 and 177 °C. The apparent activation energies of the first exothermic decomposition peaks of 1 and 2 are 247.2 and 185.2 kJ ·mol-1. Both 1 (35 J, > 360 N) and 2 (12.5 J, > 360 N) are less sensitive than RDX. The catalytic effects on the decomposition of ammonium perchlorate (AP) of 1 and 2 were studied by DSC. All results supported the potential applications of the energetic complexes as additives of solid rocket propellants. [ABSTRACT FROM AUTHOR]

Based on the tripodal 1,3,5-tris(imidazol-1-yl)benzene (tib) ligand, four transition metal coordination polymers, namely, {[Ni3(tib)2(H2O)12] ·(SO4)3} n ( 1), {[Co1/6(tib)1/3] ·(O)1/3} n ( 2), and [ M(tib)(hip)] n ( M = Mn for 3, and M = Co for 4) (hip = 5-hydroxyisophthalic acid), were synthesized through solvothermal method. Their structures were defined by single-crystal X-ray diffraction analyses and further characterized by elemental analyses (EA), IR spectra, powder X-ray diffraction (PXRD), and thermogravimetric analyses (TGA). Complex 1 displays a 2D 3-connected (63) hcb net. Complex 2 is a 2D (3,6)-connected (43)2(46.66.83) kgm net. Complex 3 and 4 present similar 2D 4-connected (44.62) sql net. Moreover, the solid state luminescence properties of complexes 1 and 3 were investigated. [ABSTRACT FROM AUTHOR]

Turquoise monoclinic single crystals of the novel three-dimensional Cu2[μ8-O3P(CH2)2PO3] ·3.2H2O coordination polymer were prepared using the silica gel method. Space group C2/ m (no. 12) with a = 1483.6(2), b = 668.44(8), c = 436.30(6) pm, β = 93.28(2)°. The Cu2+ cation is coordinated by four oxygen atoms stemming from the 1,2-ethylenediphosphonate dianions in a square planar manner and two water molecules in the axial positions. The connection between the Cu2+ cations and the [CPO3] units from the 1,2-ethylenediphosphonate dianions leads to layers parallel to (100), which are linked by the ethylene groups to a three-dimensional framework with channel-like voids. The channel-like voids accommodate water molecules not bound to Cu2+ and extend parallel to [001] with an opening of about 550 pm × 260 pm. Magnetic measurements reveal an antiferromagnetic behavior due to a superexchange coupling between Cu2+ ions through an oxygen bridge. The UV/Vis spectrum reveals three d-d transition bands at 694, 774, and 918 nm. The compound can be fully dehydrated by thermal treatment and rehydrated by storage in ambient air. [ABSTRACT FROM AUTHOR]

1, 1, 3, 3, 5, 5-Hexavinyl-1, 3, 5-trisilacylohexane [Si(CH=CH2)2CH2]3 was synthesized and hydrosilylated with trichlorosilane to afford the first generation of a dendrimer. Conversion of this molecule with 18 Si-Cl functions on its surface with an excess of vinylmagnesium bromide yielded the 18-fold vinylated dendrimer. The new compounds were identified by elemental analyses, multi-nuclear NMR spectroscopy, and mass spectrometry. Crystal structures were obtained for [Si(CH=CH2)2CH2]3 and [Si(CH2-CH2SiCl3)2CH2]3. [ABSTRACT FROM AUTHOR]

Two polyoxometalate-based compounds constructed by Keggin/Ag/L, namely [Ag10(L1)6(HL1)2][HPMo2 VMoVI] (1) and [Ag10O40] (1) and [Ag10(L2)8(H2SiMo12 = 1,2,4-1H-triazole and L40 = 1Htetrazole), were synthesized under hydrothermal conditions and characterized by single-crystal X-ray diffraction, elemental analyses, and IR spectroscopy. In compound 1, the tetra-nuclear Ag cycles constructed by four L1 ligands, two Ag1 ions, and two Ag2 ions. Com- pound 1 exhibits a two dimensional (2D) metal-organic layer containing adjacent tetra-nuclear Ag cycles. Furthermore, the adjacent 2D layers are further extended by Ag ions to form a three dimensional (3D) channel-like framework, with Keggin anions embedding in the channels. Compound 2 is isostructural with 1. Additionally, the electrochemical and photocatalytic properties of the title compounds were investigated. [ABSTRACT FROM AUTHOR]2 = 1Htetrazole), were synthesized under hydrothermal conditions and characterized by single-crystal X-ray diffraction, elemental analyses, and IR spectroscopy. In compound 1, the tetra-nuclear Ag cycles constructed by four L1 ligands, two Ag1 ions, and two Ag2 ions. Com- pound 1 exhibits a two dimensional (2D) metal-organic layer containing adjacent tetra-nuclear Ag cycles. Furthermore, the adjacent 2D layers are further extended by Ag ions to form a three dimensional (3D) channel-like framework, with Keggin anions embedding in the channels. Compound 2 is isostructural with 1. Additionally, the electrochemical and photocatalytic properties of the title compounds were investigated. [ABSTRACT FROM AUTHOR]

Three coordination polymers, namely {[Cu(5-nipa) (L22)](H2O)2}n (1), [Zn(5-nipa)(L22)(H2O)]n (2), and {[Cd2(5-nipa) 2(L22)(H2O)3](H2O)3.6}n (3), were prepared under similar synthetic method based on 1,2-(2-pyridyl)-1,2,4-triazole (L22) and ancillary ligand 5-nitro-isophthalic acid (5-H2nipa) with CuII, ZnII, and CdII perchlorate, respectively. All the complexes were characterized by IR spectroscopy, elemental analysis, and powder X-ray diffraction (PXRD) patterns. Single-crystal X-ray diffraction indicates that complexes 1 and 2 show similar 1D chain structures, whereas complex 3 exhibits the 2D coordination network with hcb topology. The central metal atoms show distinct coordination arrangements ranging from distorted square-pyramid for CuII in 1, octahedron for ZnII in 2, to pentagonal- bipyramid for CdII in 3. The L22 ligand adopts the same (η3,μ2) coordination fashion in complexes 1-3, while the carboxyl groups of co-ligand 5-nipa2- adopt monodentate fashion in 1 and 2 and bidentate chelating mode in 3. These results indicate that the choice of metal ions exerts a significant influence on governing the target complexes. Furthermore, thermal stabilities of complexes 1-3 and photoluminescent properties of 2 and 3 were also studied in the solid state. [ABSTRACT FROM AUTHOR]

A mixed-valence Mn complex {[MnIIMnIII(HL)2(4,4′-bpy)(H2O)2] ·(ClO4)(DMF)3(4,4′-bpy)0.5} n ( 1) [H2L = 3-(2-phenol)-5-(pyridin-2-yl)-1,2,4-triazole] was synthesized and characterized by X-ray single-crystal structure analysis and magnetic susceptibility. Single-crystal X-ray analysis revealed that complex 1 has a dinuclear core, in which adjacent central MnIII atoms are linked by 4,4′-bipyridine to form an infinite one-dimensional (1D) molecular configuration. According to the Mn surrounding bond lengths and bond valence sum (BVS) calculations, we demonstrated that the Mn atom coordinated to the pyridine N atoms is in the +2 oxidation state, while another Mn atom coordinated to the phenolic oxygen atoms is in the +3 oxidation state. Magnetic susceptibility data of the complex 1 indicate that the ferromagnetic interaction dominates in this complex. [ABSTRACT FROM AUTHOR]

Four Ln-NDC coordination polymers [ Ln(NDC)(HNDC)(H2O)] ( Ln = La ( 1), Pr ( 2), Nd ( 3), Sm ( 4), H2NDC = 1,4-naphthalenedicarboxylic acid) were hydrothermally synthesized and structurally characterized by elemental analyses, IR spectroscopy, and single-crystal X-ray diffraction. Compounds 1- 4 are isomorphous, and their structures display a layer constructed from a Ln-organic chain and NDC2- ligand, in which the H2NDC ligands adopt two different acidity-dependent types and coordination modes: HNDC1- with μ-η1:η1 and NDC2- with μ-η1:η2:η1:η2. The 3D supramolecular networks of 1- 4 are mainly controlled by hydrogen bonds interactions. The magnetic susceptibilities of complexes 2- 4 reveal overall antiferromagnetic interactions between the LnIII ions. In addition, thermogravimetric analysis of compound 2 is described. [ABSTRACT FROM AUTHOR]

Deprotonation of 1,2-bis(neopentylamino)benzene ( 1) with an excess of KH in tetrahydrofuran (thf) yields the singly metalated derivative [(thf)K{C6H4-1-(NH-CH2 tBu)-2-(N-CH2 tBu)}] ( 2a). Performance of the metalation reaction in tetrahydropyran (thp) leads to formation of [(thp)2K{C6H4-1-(NH-CH2 tBu)-2-(N-CH2 tBu)}] ( 2b). The second amino group of 2a can be lithiated by butyllithium yielding heterobimetallic [(thf)2LiK{C6H4-1,2-(N-CH2 tBu)2}] ( 3). The structures demonstrate that ethers as well as aromatic π systems represent suitable bases for the rather soft potassium ions. Intermolecular potassium π interactions lead to the formation of strands in the crystalline state. For complex 2a, a dynamic exchange process of the N-bound hydrogen atom with an energy barrier of 45.6 kJ ·mol-1 is observed in [D8]THF solution. Heterobimetallic 3 also shows a temperature-dependent dynamic behavior that gives rise to splitting of the methylene and aromatic resonances suggesting overlying metal exchange and aggregation equilibria. [ABSTRACT FROM AUTHOR]

Three ternary rare earth [NdIII ( 1), SmIII ( 2) and YIII ( 3)] complexes based on 3-[(4,6-dimethyl-2-pyrimidinyl)thio]-propanoic acid (HL) and 1,10-phenanthroline (Phen) were synthesized and characterized by IR and UV/Vis spectroscopy, TGA, and single-crystal X-ray diffraction. The crystal structures showed that complexes 1- 3 contain dinuclear rare earth units bridged by four propionate groups and are of general formula [ REL3(Phen)]2 · nH2O (for 1 and 2: n = 2; for 3: n = 0). All rare earth ions are nine-coordinate with distorted mono-capped square antiprismatic coordination polyhedra. Complex 1 crystallizes in the monoclinic system, space group P21/ c with a = 16.241(7) Å, b = 16.095(7) Å, c = 19.169(6) Å, β = 121.48(2)°. Complex 2 crystallizes in the monoclinic system, space group P21/ c with a = 16.187(5) Å, b = 16.045(4) Å, c = 19.001(4) Å, β = 120.956(18)°. Complex 3 crystallizes in the triclinic system, space group P1 with a = 11.390(6) Å, b = 13.636(6) Å, c = 15.958(7) Å, α = 72.310(17)°, β = 77.548(15)°, γ = 78.288(16)°. The antioxidant activity test shows that all complexes own higher antioxidant activity than free ligands. [ABSTRACT FROM AUTHOR]

Hydrothermal reactions of Cd(OAc)2 ·2H2O with 1,2-naphthalic anhydride in the absence/presence of different rigid/flexible bis(pyridyl) co-ligands, produce three distinct coordination polymers, namely [Cd(ndc)] n ( 1), {[Cd5(ndc)4(bpp)2(OH)2](H2O)4} n ( 2), and [Cd5(ndc)4(bpy)2(OH)2] n ( 3) [ndc = 1,2-naphthalenedicarboxylate, bpp = 1,3-bis(4-pyridyl)propane, and bpy = 4,4′-bipyridine]. Complex 1 contains dinuclear [Cd2O2] clusters as secondary building units (SBUs) and shows a two-dimensional (2D) kgd network. Complexes 2 and 3 possess one-dimensional (1D) chains based on pentanuclear [Cd5(μ3-OH)2(COO)2] units as SBUs, which are further extended to afford 2D sql sheet via flexible bpp in 2 and three-dimensional (3D) pcu network via rigid bpy in 3, respectively. The structural diversities indicate that the bis(pyridyl) co-ligands with different flexibility play a key role on the formation of the final supramolecular structures. The complexes were characterized by X-ray crystallographic, IR, elemental, thermal stability, and powder X-ray diffraction analyses. In addition, the photoluminescent properties in solid state were also investigated. [ABSTRACT FROM AUTHOR]

An aluminum(III) monohydride [(2, 6- iPr2C6H3)NC(Me)]2AlH(NMe3) ( 1) was synthesized by oxidative addition of 1, 2-diimine (L) {L = [(2, 6- iPr2C6H3)NC(Me)]2} with equivalent amounts of H3Al ·NMe3. A lithium salt (LLi2) was obtained when L was treated with elemental lithium. Under these conditions 1, 2-diimine is reduced to LLi2 with simultaneous formation of a C=C bond. The LLi2 is formed in-situ and treated with AlBr3 to result in the formation of aluminum(III) monobromide [(2, 6- iPr2C6H3)NC(Me)]2AlBr(OEt2) ( 2). The two products 1 and 2 show a saturated as well as an unsaturated backbone of the ligand. [ABSTRACT FROM AUTHOR]

Three coordination networks with the 1, 2,4-triazole linking units 3-(4′-imidazole phenyl)-5-(pyrid-2′′-yl)-1, 2,4-triazole (HIppyt) and 3-(pyrazin-2′-yl)-5-(4′-(pyrid-4′′-yl)-phenyl)-1, 2,4-triazole (Hpypypt), respectively, were synthesized and structurally characterized. The structures of [Mn(Ippyt)2 ·2H2O] ( 1) and [Zn(Ippyt)2 ·2H2O] ( 2) were found to be similar despite the presence of different metal ions. When Ippyt was replaced by pypypt to react with Zn(OAc)2 ·2H2O, the 2D coordination polymer, {[Zn(pypypt)2] ·2DMF} n ( 3) formed. The adjacent zinc(II) atoms with similar octahedral coordination environment are interlinked by four separate pypypt ligands to construct a 2D network structure. The biological activities of 1 and 3 were studied. The results indicate that 1 and 3 exhibit certain antimicrobial activities. Furthermore, solid-state properties of thermal stability and photoluminescence properties at room temperature for these crystalline materials were also investigated. [ABSTRACT FROM AUTHOR]

Ionothermal reactions of Ln(NO3)3 [ Ln = Eu ( 1), Sm ( 2)] with 1, 4-naphthalenedicarboxylic acid (1, 4-H2ndc) and oxalic acid (H2ox) in 1-ethyl-3-methylimidazolium bromide (EMIM-Br) ionic liquid (IL) afforded two lanthanide compounds, namely, {(EMIM)[ Ln(1, 4-ndc)(ox)0.5Br]} n [ Ln = Eu ( 1), Sm ( 2)]. The two isomorphous compounds consist of anionic three-dimensional lanthanide-carboxylate frameworks and extraframework charge-balancing species of [EMIM]+ cations. Both compounds are 6-connected pcu topological nets based on the dinuclear lanthanide secondary building units. It is noted that the cationic and anionic components of the IL are incorporated into the structures under the present ionothermal conditions. Moreover, the use of IL solvent for preparation of the lanthanide compounds can prevent the coordination of water and organic solvent molecules from central lanthanide atoms effectively. Detailed photoluminescence studies showed both compounds exhibit typical lanthanide luminescent emissions. An efficient excitation energy transfer from organic ligand-to-EuIII ion is observed in compound 1. [ABSTRACT FROM AUTHOR]