Synthesis and spectral studies of macrocyclic Pb(Ⅱ),Zn(Ⅱ),Cd(Ⅱ)and La(Ⅲ) complexes derived from 1,4-bis(3-aminopropoxy)butane with metal nitrate and salicylaldehyde derivatives

Eight new macrocyclic complexes were synthesized by template reaction of 1,4-bis（3-aminopropoxy）butane with metal nitrate and 1,3-bis（2-formylphenyl）propane or 1,4-bis（2-formylphenyl）butane and their structures were proposed on the basis of elemental analysis, FTIR, UV-vis, molar conductivity measurements, ^1H NMR and mass spectra. The metals to ligand molar ratios of the complexes were found to be 1： 1. The complexes are 1：2 electrolytes for Pb（II）, Zn（II） and Cd（II） complexes and 1：3 electrolytes for La（III） as shown by their molar conductivities （Am） in DMSO at 10^-3 mol L^-1. Due to the existence of free ions in these complexes, such complexes are electrically conductive. The configurations of La（III） and Pb（II） were proposed to probably octahedral and Zn（II） and Cd（II） complexes were proposed to probably tetrahedral.

Heterometallic Trinuclear Ni_2Zn and Ni_2Mn Complexes of Macrocyclic Oxamide: Synthesis and Crystal Structures

Two novel heterometallic trinuclear complexes of macrocyclic oxamide [Mn（NiL）2（HBTC）H2O] （1） and [Zn（NiL）2（HBTC）H2O] （2） （NiL, H2L = 2,3-dioxo-5,6,14,15-dibenzo-1,4,8,12-tetraazacyclo-pentadeca-7,13-dien, H3BTC = 1,3,5-benzenetricarboxylic acid） have been solvothermally synthesized and structurally characterized by elemental analysis, IR spectroscopy and single-crystal X-ray diffraction. For 1, the crystals crystallize in the monoclinic system, space group P21/c with a = 11.3595（5）, b = 23.1498（11）, c = 17.2558（8） and =101.2530（10）°. For 2, the crystals crystallize in the monoclinic system, space group P21/c with a = 11.5214（8）, b = 20.6566（14）, c = 18.4126（13） and = 92.6770（10）°. The structures of 1 and 2 have oxamido-bridged trinuclear [NiⅡ2MⅡ] units and consist of two-dimensional supramolecular architectures formed by strong O–H…O intermolecular hydrogen bonds.

Synthesis and Characterization of Two Binuclear Macrocyclic Zinc(Ⅱ) Complexes by Anion Exchange

Two macrocyclic zinc（Ⅱ） complexes {[ZnL（VO3）2]·0.33H2O}n（1） and [ZnL（H2O）2][Ni（CN）4]（2）（L = 5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane） have been obtained from the reactions of [ZnL]（ClO4）2 with NH4VO3 and K2[Ni（CN）4], respectively, and structurally characterized by elemental analysis, IR, XRPD, TG and X-ray diffraction. Single-crystal X-ray diffraction analyses indicated that the Zn（Ⅱ） atom lies on an inversion center and is octahedrally coordinated by four nitrogen atoms of the tetradentate macrocyclic ligand in the equatorial plane and two oxygen atoms of [VO4] tetrahedra in the axial positions in 1, and two oxygen atoms of two water molecules in 2. Complex 1 shows a three-dimensional structure, which is constructed by the links of [VO3]nn- chains with [ZnL]2＋, forming one-dimensional channels occupied by guest water molecules. The monomers of [ZnL（H2O）2]2＋ and [Ni（CN）4]2- are connected through the intermolecular hydrogen bonds to form a two-dimensional sheet in complex 2.

Chiral Resolution of β-dl-Phenylalanine Using Chiral Macrocyclic Nickel(Ⅱ) Complexes

The reactions of chiral four-coordinated nickel（Ⅱ） complex [Ni（RR-L）]（ClO4）2/[Ni（SS- L）]（ClO4）2 with β-dl-phenylalanine in acetonitrile/water gave a six-coordinated enantiomer of [Ni（RR-L）（β-d-HPhe）]（ClO4）2（1） and [Ni（SS-L）（β-l-HPhe）]（ClO4）2（2）, respectively（L = 5,5,7, 12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane, HPhe = phenylalanine）. Single-crystal X-ray diffraction analyses revealed that the nickel（Ⅱ） atom displays a distorted octahedral coordination geometry by coordinating with four nitrogen atoms of L in a folded configuration, and two carboxylate oxygen atoms of β-d/l-HPhe in cis-position in both complexes. The monomers of [Ni（RR-L）（β-d-HPhe）]2＋ and [Ni（SS-L）（β-l-HPhe）]2＋ are connected through intermolecular hydrogen bonds to generate one-dimensional zigzag chains, respectively. The homochiral natures of 1 and 2 are confirmed by the results of CD spectroscopy.

Synthesis and Characterization of Binuclear Lanthanide Complexes with Macrocyclic Schiff Base Derived From 2,6-Diacetylpyridine and 1,3-Diamino-2-hydroxypropane

Nine homobinuclear lanthanide complexes with macrocyclic Schiff base were prepared by condensing 2, 6-diacetylpyridine and 1, 3-diamino-2-hydroxypropane in the presence of template lanthanide metal ions. These complexes were characterized by elemental analysis, IR, molar conductance and magnetic susceptibility. The variable-temperature magnetic susceptibility (4-300 K) of complexes of Gd( Ⅲ ) and Dy( Ⅲ ) was determined. A satisfactory fit to theoretical curve derived from spin Hamiltonian operator was obtained using least-squares method. The exchange interaction parameters are J=-0.26 cm-1, g=1.98 and △=0.06 cm-1, Z.J'=-0. 21 cm-1,g'=1.33 for Gd( Ⅲ ) and Dy( Ⅲ ), respectively. The results indicate a very week antiferromagnetic interaction between Gd( Ⅲ )-Gd( Ⅲ ) and Dy( Ⅲ )-Dy( Ⅲ ) ions.

Syntheses and Structures of Two Macrocyclic Nickel(Ⅱ) Complexes Bridging Benzene Polycarboxylic Acid

Two complexes with formulas [Ni L][（Ni L）（IPA）2]·8H2O（1） and [（Ni L）（H2O）2] [（Ni L）（PMA）]·4H2O（2）（L = 5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane,IPA2– = isophthalic anion,PMA4– = 1,2,4,5-benzenetetracarboxylic anion） were synthesized and characterized by elemental analyses and IR spectra.The crystal structures were determined by X-ray diffraction.In complex 1,the [Ni L]^2＋ bridged IPA^2– to give [（Ni L）（IPA）2]^2– monomer,and the [Ni L]^2＋ bridged PMA4– to form a one-dimensional chain [（Ni L）（PMA）]n^2n– in complex 2.The [Ni L]^2＋ and [（Ni L）（IPA）2]^2–/[（Ni L）（PMA）]^2– are connected through intermolecular hydrogen bonding to generate three-dimensional supramolecular structures.

Syntheses and Structures of Three Hybrid Materials Using Vanadium Polyoxoanions and Macrocyclic Copper Complex as Building Blocks

The reactions of the four-coordinated macrocyclic copper complex [CuL]（ClO4）2（L = 1,4,8,11-tetraazacyclotetradecane） with NH4VO3 under different conditions gave three inorganic-organic hybrid materials of [CuL][VO3]2·2.33H2O（1）, [CuL]3[V（10）O（28）]·8H2O（2） and [Cu L]3[V6O（18）]·8H2O（3）. Single-crystal X-ray diffraction analyses reveal that three diverse vanadium polyoxoanions, [V6O（18）]6- ring, [V（10）O（28）]6- cluster, and [V（12）O（35）]^10- ring, were isolated from the same reactant NH4VO3 under different conditions. The [CuL]^2＋ bridges the [V10O28]6- clusters to form a two-dimensional sheet in 2, and link the [V6O（18）]^6- rings in 1 and [V（12）O（35）]^10- rings in 3 into three-dimensional frameworks, respectively.

Syntheses and Structures of Two Coordination Polymers Containing Macrocyclic Oxamide and Isophthalic Acid Derivatives

Two novel coordination polymers [Cd（NiL）（aipt）]（1） and [Mn（nipt）（NiL）2]？H2O（2）（NiL, H2L=2,3-dioxo- 5,6,14,15-dibenzo-1,4,8,12-tetraazacyclo-pentadeca-7,13-dien, H2aipt=5-aminoisophthalic acid, H2nipt=5-nitroisoph- thalic acid） were hydrothermally synthesized and characterized by single-crystal X-ray diffraction. Compounds 1 and 2 consist of different 1D chains including both oxamide and 5-aminoisophthalate or 5-nitroisophthalic bridge. And all these chains were further interlinked via hydrogen bonds, resulting in a 2D architecture in compounds 1 and 2.

Molecular and Supramolecular Structures of a Nickel(Ⅱ) Complex with a Macrocyclic Ligand

The crystal structure of the title complex, [NiL], has been determined by using X-ray analysis (H2L = 2,3-dioxo-5,6:13,14-dibenzo-7,12-bis(methoxycarbonyl)-1,4,8,11-tetraazacyclotetra- deca-7,11-diene). Crystal data: C22H18N4O6Ni, Mr = 493.11, triclinic, space group P, a = 9.128(6), b = 9.941(7), c = 12.396(8) ? a = 107.11(1), b = 106.14(1), g = 97.69(1), V = 1003.9(11) 3, Z = 2, Dc = 1.631 g/cm3, m(MoKa) = 1.018 mm-1, F(000) = 508, R = 0.0584 and wR = 0.0981 for 1724 observed reflections with I > 2s(I). The Ni(II) atom is coordinated by four nitrogen donors of the macrocyclic ligand with a slightly distorted square-planar geometry. In the crystal, the CH…O hydrogen bonds link the complex molecules to form infinite 1D chains which are further linked by p…p stacking interactions to form chain-pairs.

Synthesis, Crystal Structure, DNA Binding and Catalytic Activities of a New Unsymmetrical Macrocyclic Dinuclear Zn(Ⅱ) Complex

An unsymmetrical macrocyclic dinuclear Zn（II） complex, [Zn2（H0.5L）（OAc）]（ClO4）1.5（1, H2 L is the condensation product between 2, 6-diformyl-4-methylphenol and diethylenetriamine）, was obtained and characterized by IR spectrum, elemental analysis and X-ray single-crystal diffraction. The complex crystallizes in monoclinic, space group P21/c with a = 16.784（2）, b = 19.474（3）, c = 10.3364（13）A, β = 92.923（2）°, V = 3374.1（7） A3, Z = 4, Dc = 1.672 g/cm^3, F（000） = 1740, μ = 1.651 mm^-1, the R = 0.0609 and wR = 0.1696 for 4745 observed reflections（I 〉 2σ（I））. The interactions of the complex with DNA have been measured by electrochemical studies, UV spectroscopy and viscosity experiment. The interactions of the complex with calf thymus DNA were studied by UV-vis spectra and the binding constant is 1.58 × 10^4 mol·L^-1. The phosphate hydrolysis catalyzed by the complex was investigated using 4-nitrophenyl phosphate（NPP） as the substrate; the observed first order rate constant value is 3.0 × 10^–4 s^-1.

Synthesis and Crystal Structure of Unprecedented Pentanuclear Cu_5~Ⅱ Complex Containing both Macrocyclic and Azido Ligands

The organic-inorganic hybrid complex with formula [（CuL）2Cu3（μ-1,1-N3）4（ClO4）2], complex 1, {CuL, [5,6：14,l5-dibenzo-1,4,8,12-tetraazacyclopentadeca-7,3-diene-2,3-dione（2-）]copper（Ⅱ）}, has been synthesized and structurally determined. The crystals of complex 1 crystallize in the triclinic system with space group P1, a=0.92983（12） nm, b=1.09644（14） nm, c=1.27396（16） nm, α=70.782（2）°β=86.266（2）°,γ=78.284（2）°. In this complex, the five copper ions are bridged by macrocyclic oxamide groups and azido. Furthermore, C-H…O hydrogen bond interactions link the pentanuclear fragments to form a 2D supramolecular architecture.

Crystal Structure and Magnetic Properties of the Oxamidato-bridged Cu_3 Complex Containing Macrocyclic Ligands

One novel oxamido-bridged trinuclear complex [Cu（CuL）2（ClO4）2] has been syn-thesized and structurally determined.It crystallizes in the monoclinic system,space group P21/n with a = 10.636（4）,b = 11.645（4）,c = 16.038（6） ,β = 91.029（5）°,V = 1986.2（12） 3,C38H32Cl2Cu3N8O12,Mr = 1054.24,Dc = 1.763 Mg/m3,μ（MoKα） = 1.802 mm-1,F（000） = 1066,Z = 2,the final R = 0.0328 and wR = 0.0882 for 3152 observed reflections.The crystal structure is a trinuclear complex in which the CuII ions are bridged by macrocyclic oxamide groups.C-H···O hydrogen bonding interactions link the trinuclear fragment to form a 2D supramolecular architecture.Magnetic measurements indicate that the compound is moderately antiferromagnetically coupled.

A Kinetic Study on Dismutation of Superoxide Ion by Macrocyclic Dioxotetramine-Copper(Ⅱ) Complex by Using Pulse Radiolysis

We studied the reaction kinetics of dismutation for superoxide ion by copper (Ⅱ) complex of macrocycllc dioxotetramine ligand 12- ( 4' - nitro )- benzyl-1,4,7,10- tetraazacy-clotridecane-11,13-dionato copper (Ⅱ) by using pulse radiolysis. The rate constants of dismutation kcat's were measured to be 1. 78×106 mor-1 . L.s-1(at pH 7. 0) and 1. 06×106 mol-1. L. s-1(at pH 7. 8). The reaction mechanism is similar to that catalyzed by super-oxide dismutase.

Unexpected Synthesis and Crystal Structure of Macrocyclic Nickel Complex Involving Rare S-Cl Bond

A novel complex of [NiL（OOCNH2C2H3SClO3）]·H2O was obtained unexpectedly by the reaction of [Ni（rac-L）]（ClO4）2 with l-cysteine （L=5,5,7,12,12,14-hexamethyl-1,4,8,11-tetra- azacyclotetradecane）, and characterized by EA, IR, ESI-MS and single-crystal X-ray diffraction. It crystallizes in the orthorhombic system, space group P212121 with a=9.211（12）, b=14.942（19）, c=19.002（2）, Mr=563.80, V=2615.3（6）3 , Z=4, Dc=1.432 g/cm3 , F（000）=1204, μ=0.966 mm-1 , the final R=0.0565 and wR=0.1515. The central nickel（Ⅱ） ion displays a distorted six-coordinate octahedral coordination geometry by coordination with four nitrogen atoms of L, and one oxygen and one nitrogen atoms of l-cysteine. The sulfur atom of l-cysteine instead of oxygen atom links directly with the chlorine atom of perchlorate. The title complex is the first example of perchlorate salt involving the sulfur atom.

Transition metal-nitrogen sites for electrochemical carbon dioxide reduction reaction

Electrochemical CO2 reduction reaction(CO2RR)powered by renewable electricity has emerged as the most promising technique for CO2 conversion,making it possible to realize a carbon‐neutral cycle.Highly efficient,robust,and cost‐effective catalysts are highly demanded for the near‐future practical applications of CO2RR.Previous studies on atomically dispersed metal‐nitrogen(M‐Nx)sites constituted of earth abundant elements with maximum atom‐utilization efficiency have demonstrated their performance towards CO2RR.This review summarizes recent advances on a variety of M‐Nx sites‐containing transition metal‐centered macrocyclic complexes,metal organic frameworks,and M‐Nx‐doped carbon materials for efficient CO2RR,including both experimental and theoretical studies.The roles of metal centers,coordinated ligands,and conductive supports on the intrinsic activity and selectivity,together with the importance of reaction conditions for improved performance are discussed.The mechanisms of CO2RR over these M‐Nx‐containing materials are presented to provide useful guidance for the rational design of efficient catalysts towards CO2RR.

A study on some macrocyclic bicopper(Ⅱ) complexes as the model compounds of superoxide dismutase

24-Membered macrocyclic bicopper(Ⅱ) complexes wth bridging ligand imidzao-late,SCN-,N3-and H2O respectively were synthesized by condensation of diacetylpyridine with 3-oxapentane-1,5-diamine.As the model compounds of superoxide dismutase (SOD),the relationship between their SOD activities and properties of bridging ligands and redox potentials of copper(Ⅱ) were studied.

The First Example of Inorganic-organic Compound Involving the Largest Vanadium Cluster of [V_(34)O_(82)]^(10-): Hydrothermal Synthesis and Characterization of a One-dimensional Chain of {[NiC_(16)H_(36)N_4]_5[V_(34)O_(82)]}_n

The title compound, [NiL]5[V34O82·8H2O （1, L=5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane）, has been synthesized under hydrothermal conditions and structurally characterized by EA, IR, XPS, TG and single-crystal X-ray diffraction. It crystallizes in the monoclinic system, space group C2/c with a=33.061（4）, b=15.3457（17）, c=33.902（4）, β=101.930（2）°, Mr=4904.08, V=16828（3）3 , Z=4, Dc=1.936 g/cm3 , F（000）=9832, μ=2.425 mm-1 , the final R=0.0402 and wR=0.0969. The mixed valence vanadium clusters of [V34O82]10- bridges [NiL]2＋ to form a one-dimensional chain in 1. To the best of our knowledge, the title complex is the first example of organic-inorganic hybrid material involving the largest vanadium cluster of [V34O82]10-.

Syntheses and structures of tetranuclear Zn(Ⅱ) complexes with in situ generated macrocyclic Schiff base ligands:Applications in Zn^(2+) sensing

Three novel Zn（II） complexes,[Zn4L1Cl4]-3H2O（1）,[Zn4L2Cl4]-2DMF（2） and[Zn4L^3Cl4]H2O（3）,have been synthesized and structurally characterized.In these complexes,interesting 32-membered dodecadentate macrocyclic ligands were generated in situ by ＇2 ＋ 2＇ type condensation reactions between a tetraamine and various dialdehydes.All the complexes are isostructurally tetranuclear Zn（Ⅱ） complexes,containing endogenous alkoxo and phenoxo bridges.Applications of the macrocyclic ligands as Zn^2＋ sensors have been investigated.Take H4L^1 for example,it exhibits a 4-fold fluorescence enhancement upon the addition of 2 equiv.of Zn^2＋ in MeOH.

A Study on Complex of 1-Oxa-4,7,10-Triazacyclododecane( Ⅱ )——The Syntheses, Properties and Crystal Structure of Its Manganese( Ⅱ ) Thiocyanate Complex

Introduction The substitution of atom N for O in macrocyclic crown ether greatly influences its complexation. It is just expected that the complexing effects of the substituted macrocyclic on transition metals are greatly increased. The present paper covers the synthesis, structure and characterization of the complex [MnL（NCS）;] of title macrocyclic ligand (L is 1-oxa-4, 7, 10-triazacy-

Crystal Structure of a Copper(II) Complex with 2,3-Dioxo-5,6:13,14-dibenzo-9-methyl-7,12-bis(ethoxycarbonyl)-1,4,8,11-tetraazacyclotetradeca-7,11-diene

The molecular and crystal structure of a macrocyclic N,N′-substituted- oxamidocopper(II) complex, [CuL], where H2L = 2,3-dioxo-5,6:13,14-dibenzo-9-methyl-7,12- bis(ethoxycarbonyl)-1,4,8,11-tetraazacyclotetradeca-7,11-diene, has been determined by X-ray diffraction method. Crystal data: C25H24CuN4O6, Mr = 540.02, monoclinic, space group C2/c, a = 25.605(4), b = 9.230(2), c = 22.105(4) ?, ( = 111.749(4)(, V = 4852(2) ?3, Z = 8, Dc = 1.478 g/cm3, μ (Mo-K() = 0.949 mm-1, F(000) = 2232, R = 0.0681 and wR = 0.1666 for 2747 observed reflections with I ( 2((I). The copper atom is located in the coordination cavity formed by the four nitrogen donors of the deprotonated macrocyclic oxamido ligand with a distorted square-planar geometry. In the crystal, two molecules are connected by the Cu···O weak coordination bonds to produce a supramolecular quasi-dimer.