3D Cadmium Research Articles

A 3D cadmium(II) coordination polymer constructed from new β-diketone-functionalized pyridinecarboxylate and 4,4′-bipyridine ligands

A new cadmium(II) coordination polymer [Cd2(L)2(bpy)]n·nCH3OH (1) (H2L=2-(3-oxo-3-phenylpropionyl)-6-pyridinecarboxylic acid N-oxide, bpy=4,4′-bipyridine), has been synthesized from the reaction of H2L, 4,4′-bipyridine with CdSO4·8/3H2O. Compound 1 is an exceptional non-interpenetrating three-dimensional framework and contains double helical chains and rare cross bpy configuration. Interestingly, these helical chains can span two different directions on other alternate layers. Compound 1 shows intense photoluminescence at room temperature.

Two three-dimensional cadmium(ii) coordination polymers based on 5-amino-tetrazolate and 1,2,4,5-benzenetetracarboxylate: the pH value controlled syntheses, crystal structures and luminescent properties

Two 3D cadmium(ii) coordination polymers have been prepared by controlling the pH values of the reaction mixture.

Selective pyridine recognition by an imidazole dicarboxylate-based 3D cadmium(ii) MOF

One newly prepared 3D polymer (1) composed of left- and right-handed helices containing [Cd8(p-ClPhHIDC)12(4,4′-bipy)6] cages shows selective pyridine recognition, with a visual colour change from pearl to pink under ultraviolet irradiation.

Synthesis, Structure and Properties of a 2D Cadmium(II) Coordination Polymer Based on Fluconazole and Isophthalate Ligands

A Cd(II) complex based on fluconazole and isophthalate ligands, {[Cd(HFlu)(IPA)(H2O)] · H2O}n (1), (HFlu=fluconazole; H2IPA=isophthalic acid) has been synthesized. Single-crystal X-ray analysis reveals that complex 1 has a 2D network structure including unusual triple hydrogen bonds between hydroxyl and triazolyl groups. The complex has also been characterized by IR, UV=Vis and fluorescence spectroscopy, elemental analysis, and thermogravimetry

Construction of a New 2D Cadmium(II) Coordination Polymer Based on N- and O-Donor Ligands: Synthesis, Luminescence and Biological Activities

A new 2D Cd(II) coordination polymer, {[Cd(4-cpa) (bpp)2H2O]·(4-cpa)·(H2O)} n (1) [4-cpa = 4-chlorophenoxyacetate, bpp = 1,3-bis(4-pyridyl)propane] has been hydrothermally synthesized and characterized by elemental analysis, IR-spectroscopy, thermogravimetric analysis, powder X-ray diffraction and single-crystal X-ray diffraction. Complex 1 consists of discrete 2D cadmium complex, 4-cpa counter ions and free water molecules, which are assembled into a 3D supramolecular structure through hydrogen bonds and π···π stacking interactions. Three-dimensional fluorescence spectra of 1 were detected at room temperature under the excitation and the emission wavelengths in the range of 300–600 nm with the interval of 5 nm. The lifetime of the excited state of 1 upon excitation of 443 nm in solid-state at room temperature is 30.21 ns. The 4-cpa ligand and complex 1 have been screened for their phytogrowth-inhibitory activities against Brassica campestris L. and Echinochloa utilis Ohwi et Yabuno, and the results are compared with the activity of sodium 2,4-dichlorophenoxyacetate. Hydrothermal synthesis of a new 2D Cd(II) coordination polymer, {[Cd(4-cpa) (bpp)2H2O]·(4-cpa)·(H2O)} n (1) [4-cpa = 4-chlorophenoxyacetate, bpp = 1,3-bis(4-pyridyl)propane] leading to a material that displays intense blue 3D luminescence properties and phytogrowth-inhibitory activities.

A flexible multidentate Schiff-base ligand having multifarious coordination modes in its copper(II) and cadmium(II) complexes

A mononuclear complex, [CuL2]·2(CH3OH) (1), and two one-dimensional (1D) coordination polymers, {[Cu3L4(CH3OH)2]·(NO3)2}n (2) and [Cd(LH)2(N3)2]n (3), having a flexible multidentate Schiff-base ligand, 2-(3-(1H-imidazol-1-yl)propyliminomethyl)phenol (LH), with multifarious coordination modes have been obtained in different solvents and pH values. Another 1D cadmium(II) coordination polymer, [Cd(apimH)2Br3]n (4) (apim=(3-aminopropyl)imidazole), is also included for comparison. A four-coordinate square-planar Cu(II) center is formed in 1 where L serves as a bidentate N,O-chelating ligand, while two five-coordinate dinuclear Cu(II) centers and one six-coordinate mononuclear Cu(II) center are alternately arranged via two tridentate ligands in 2. In contrast, six-coordinate Cd(II) centers are constructed in 3 and 4, in the absence of a base, and they are bridged by double μ2 azide anions in an end-to-end way in 3 and alternate mono and triple μ2 bromine anions in 4. Furthermore, FT-IR, 1H NMR, UV–Vis and fluorescence spectral comparisons between LH and its metal complexes have been studied.

A new 3D cadmium(II) coordination polymer having μ4-oxalato, μ-aquo and μ-chlorido bridges: Crystal structure, solid state fluorescence and thermal behavior

A new 3D cadmium(II) coordination polymer, [Cd(C2O4)0.5Cl(H2O)]n (1) has been synthesized from a mixture of CdCl2. H2O and (NH4)2C2O4 in a slightly acidic pH. Its molecular structure was determined by single crystal X-ray diffraction which reveals that the new polymeric structure consists of simultaneous μ4-oxalato, μ-aquo, and μ-chlorido bridges between the metal centers, embedded in distorted pentagonal bipyramidal geometries. On thermal analysis compound exhibits high thermal stability up to 330°C. Compound 1 also exhibits strong fluorescent emission.

Crystal structural and thermal properties of a 1D cadmium coordination polymer [Cd(PhCOO)2(bbbm)] n

A new 1D cadmium coordination polymer [Cd(PhCOO)2(bbbm)] n (1) (bbbm = 1,1′-(1,4-butanediyl)bis-1H-benzimidazole ) is synthesized under hydrothermal conditions and characterized by elemental analysis, IR, TG, and X-ray single-crystal diffraction. Compound 1 crystallizes in the triclinic system, space group P-1 with a = 10.4289(17) A, b = 12.5198(9) A, c = 12.6130(9) A, α = 118.4260(10)°, β = 95.1990(10)°, γ = 94.3820(10)°, V = 1428.8(3) A3, Z = 2. In the structure of 1, each cadmium center is six-coordinated in a strongly distorted octahedron by two N and four O atoms; an infinite one-dimensional linear chain was built by the flexible bbbm ligand that adopts a bis-monodentate bridging mode linking CdII atoms.

Ligands containing pyridyl-carboxylate terminals and their discrete silver and polymeric cadmium compounds: (n-py)–CH[dbnd]N–C10H6–COOH (n = 2 (HL1), 3 (HL2)), [Ag(HL1)2](PF6), [Ag(HL1)2](NO3)(H2O), and [Cd(L2)2

Two potential linking ligands containing pyridyl-carboxylate terminals {(n-py)–CH=N–C10H6–COOH (n=2 (HL1), 3 (HL2)} were synthesized by Schiff-base condensation under solvothermal conditions in methanol. Molecules of ligand HL1 are connected by the intermolecular O–H⋯N hydrogen bonds to create a 1D zigzag network. Ligand HL1 reacted with AgPF6 and AgNO3 to produce discrete Ag(I) complexes [Ag(HL1)2](PF6) (1) and [Ag(HL1)2](NO3)(H2O) (2), respectively. Compounds 1 and 2 form a dimeric structure formed by the intermolecular O–H⋯O hydrogen bonds between two carboxylate terminals of two adjacent molecules. A 3D cadmium coordination polymer, [Cd(L2)2]∞ (3), was prepared from ligand HL2 and Cd(CH3COO)2·2H2O under solvothermal conditions. Ligand HL1 exhibited a red-shift on complex formation in its photoluminescence emission spectrum.

Crystal structure and temperature-dependent fluorescent property of a 2D cadmium (II) complex based on 3,6-dibromobenzene-1,2,4,5-tetracarboxylic acid

A new cadmium (II) organic coordination polymers [Cd(dbtec)0.5(H2O)3]·H2O (1), has been constructed based on 3,6-dibromobenzene-1,2,4,5-tetracarboxylic acid (H4dbtec), and characterized by elemental analysis (EA), infrared spectroscopy (IR), powder X-ray diffraction (PXRD), and single crystal X-ray diffraction. In 1, μ2-η1:η1 and μ4-η2:η2 dbtec ligands link four hepta-coordinated CdII ions to form a 2D 44 topological layer structure, which is further connected into an interesting 3D network by hydrogen bond and Br⋯O halogen bond. Moreover, the thermal stabilities, solid ultraviolet spectroscopy and temperature-dependent fluorescent properties of 1 were investigated.

Assembly of 1D Cadmium(II) Coordination Polymer with Bis(2-benzimidazole) and 1,3-Benzenedicarboxylic Acid Mixed Ligands

Assembly of 1D Cadmium(II) Coordination Polymer with Bis(2-benzimidazole) and 1,3-Benzenedicarboxylic Acid Mixed Ligands

A 2-fold interpenetrated 3D Cd(II) architecture with helical structure containing 1D cadmium–oxygen chain

Abstract A new 3D metal–organic framework [Cd2(2,6-pydc)2(bime)(H2O)]n (1) containing 1D Cd − oxygen chains was synthesized by the self-assembly of pyridine-2,6-dicarboxylate (2,6-pydc), 1,6-Bis (imidazol) hexane (bime) and Cd(II) salt, which exhibits a 2-fold interpenetrated 3D entanglement architecture with attractive helical structure. In addition, photoluminescent and thermal properties of complex 1 have been investigated as well.

Hydrothermal synthesis, crystal structures and photoluminescence of a 2D cadmium(II) coordination polymer based on in situ synthesized tetrazole derivative ligand

Hydrothermal reaction of methyl 4-(cyanomethoxy)benzoate, Cd(NO 3 ) 2 ·4H 2 O and NaN 3 yielded a new 2D Cd(II) coordination polymer, {[Cd 3 (N 3 ) 2 (mtzb) 4 (H 2 O) 2 ]·(H 2 O) 2.5 } n 1 (Hmtzb = methyl 4-(1 H -tetrazol-5-ylmethoxy)benzoate), which was characterized by single-crystal X -ray diffraction. The in situ [2 + 3] cycloaddition reaction of nitrile and azide in presence of Cd(II) salt afforded a new tetrazolate-based mtzbˉ ligand. In polymer 1 , The cross-linkage of the mtzbˉ ligands and Cd(II) atoms forms a 2D layer network, and the mtzbˉ ligand displays two distinct μ 3 -bridging coordination modes, μ 3 - κ N1: κ N2: κ N3 and μ 3 - κ N1: κ N2: κ N4. Photoluminescent analyses revealed that 1 exhibits a strong blue emission with a fluorescent lifetime of 3.22 ns. The relevant density of states (DOS) calculation results showed that the photoluminescence mainly originates from ligand-centered charge transition.

Synthesis, Crystal Structure, Thermal and Luminescent Characterization of Two New 3D Cadmium–Carboxylate Frameworks

Two new cadmium coordination polymers have been synthesized with composition {[Cd2(tma)(atz)(H2O)]·(H2O)} n (1) (tmaH3 = benzene-1,3,5-tricarboxylicacid, atzH = 5-aminotetrazole) and [Cd(isoor)2(H2O)2] (2) (isoorH = isoorotic acid). X-ray single crystal structure analysis reveals that complex 1 is 3D coordination polymer. However 2 is mononuclear and turned 3D via hydrogen bonding. Thermogravimetric and luminescence characterization of the complexes were done. Two new 3D coordination polymers of cadmium have been synthesized by using benzene-1,3,5-tricarboxylicacid, 5-aminotetrazole and isoorotic acid. Both the complexes are characterized by X-ray single crystal structure, thermal and photoluminescence study.

Solvothermal synthesis of CdS nanorods using poly(vinyl butyral-co-vinyl alcohol-co-vinyl acetate) as a capping agent in ethylenediamine solvent

One-dimension (1D) cadmium sulfide (CdS) nanorods were successfully synthesized using cadmium nitrate (Cd(NO3)2) and thiourea (NH2CSNH2) as starting materials and poly(vinyl butyral-co-vinyl alcohol-co-vinyl acetate) as a capping agent in ethylenediamine as a solvent by solvothermal reaction at 200°C for 24 and 72h. The phase, morphology, atomic vibration and optical property of the products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman spectroscopy and UV–visible spectroscopy. In the present research, the products were wurtzite hexagonal CdS nanorods growing along the [001] direction, with the 1LO and 2LO vibration modes at 298 and 597cm−1 and the absorption peak centered at 486nm.

Two novel 2D cadmium(ii) MOFs based on flexible bis(imidazolyl) and zwitterionic dicarboxylate ligands

The reaction of 1,4-bis((pyridinium-4-carboxylic acid)methyl)benzene dibromide (Bpmb-2HBr), Cd(NO3)2·4H2O with 1,2-bis(imidazol-1′-yl)ethane (Bime) and 1,4-bis(imidazol-1′-yl)butane (Bimb) gave rise to two novel 2D Cd(II) coordination polymers, [Cd1.5(Bime)(Bpmb)0.5(μ-Br)Br2·DMF]n (1) and [Cd2(Bimb)2(μ-Br)2Br2]n (2), respectively, in which coordination of μ-Br− and monodentate Br− with Cd(II) generates an unprecedented trimeric [Cd3(μ-Br)2Br4] unit in 1 and a dimeric [Cd2(μ-Br)2Br2] unit in 2. In 1, gauche-Bime links the central six-coordinated Cd(II) of the trimers into a 1D double chain, anti-Bpmb further bridges the terminal four-coordinated Cd(II) of the trimers in the opposite direction to generate a 2D layer. Complex 2 is a 2D corrugated layer consisting of perpendicular left- and right-handed helical chains constructed through anti-anti-gauche-conformated Bimb bridging the neighboring six-coordinated Cd(II) of [Cd2(μ-Br)2Br2] units. The thermal stability and fluorescent properties of the two complexes have also been studied.

Syntheses, crystal structures and properties of new lead(ii) or bismuth(iii) selenites and tellurite

Four new lead(II) or bismuth(III) selenites and a tellurite, namely, Pb(3)(TeO(3))Cl(4), Pb(3)(SeO(3))(2)Br(2), Pb(2)Cd(3)(SeO(3))(4)I(2)(H(2)O), Pb(2)Ge(SeO(3))(4) and BiFe(SeO(3))(3), have been prepared and structurally characterized by single crystal X-ray diffraction (XRD) analyses. These compounds exhibit five different types of structures. The structure of Pb(3)(TeO(3))Cl(4) features a three-dimensional (3D) lead(II) chloride network with tellurite anions filling in the 1D tunnels of Pb(4) 4-member rings (MRs) along the c-axis. Pb(3)(SeO(3))(2)Br(2) contains a 3D network composed of lead(II) selenite layers interconnected by bromide anions. Pb(2)Cd(3)(SeO(3))(4)I(2)(H(2)O) is a 3D structure based on 2D cadmium(II) selenite layers which are further connected by 1D lead(II) iodide ladder chains with lattice water molecules located at the 1D tunnels of the structure. Pb(2)Ge(SeO(3))(4) features a 3D framework constructed by the alternate arrangement of lead(II) selenite layers and germanium(iv) selenite layers in the [100] direction. The structure of BiFe(SeO(3))(3) is built on the 3D anionic framework of ion(III) selenite with the bismuth(III) ions located at its Fe(6)Se(6) 12-MR tunnels. Pb(3)(TeO(3))Cl(4) (Pna2(1)) is polar and BiFe(SeO(3))(3) (P2(1)2(1)2(1)) is noncentrosymmetric. Powder second-harmonic generation (SHG) measurements using 1064 nm radiation indicate that BiFe(SeO(3))(3) exhibits a weak SHG efficiency of about 0.2 × KH(2)PO(4) (KDP). Magnetic property measurements for BiFe(SeO(3))(3) show a dominant antiferromagnetic interaction with weak spin-canting at low temperatures. IR, UV-vis and thermogravimetric, as well as electronic structure calculations were also performed.

Construction of 0D to 3D cadmium complexes from different pyridyl diimide ligands

Four semirigid ditopic ligands, N,N'-bis(3-pyridylmethyl)-pyromellitic diimide (L(1)), N,N'-bis(4-pyridylmethyl)-pyromellitic diimide (L(2)), N,N'-bis(3-pyridylmethyl)-naphthalene diimide (L(3)), and N,N'-bis(4-pyridylmethyl)-naphthalene diimide (L(4)), reacted with Cd(NO(3))(2) to result in four cadmium(II) complexes, namely, {[Cd(2)(L(1))(2)(NO(3))(4)(CH(3)OH)(4)]·H(2)O} (1), [Cd(L(2))(NO(3))(2)(CH(3)OH)(2)·Cd(2)(L(2))(3)(NO(3))(4)]·{4(HCCl(3))·2H(2)O}(n) (2), {[Cd(L(3))(2)(NO(3))(2)]}(n) (3), and {[Cd(L(4))(2)(NO(3))(2)]·2(CHCl(3))}(n) (4). These complexes have been characterized by elemental analyses, powder X-ray diffraction, thermogravimetric (TG) analyses, IR spectroscopy, and single-crystal X-ray diffraction. Structural analyses show that four types of structures are formed: (1) a discrete M(2)L(2) ring with two Cd ions and two cis-L(1) ligands comprising a zero-dimensional molecular rectangle (0D), (2) an unusual zigzag linear chain and a one-dimensional ladder existing simultaneously in the crystal lattice (1D), (3) a two-dimensional network of the (4,4) net structure (2D), and (4) an unusual chiral three-dimensional framework with 5-fold interpenetrating diamond (dia) topology (3D). In these complexes, the ligands exhibit different coordination modes and construct various architectures by bridging Cd(NO(3))(2) inorganic building blocks. These results suggest that structural diversity of the complexes is tunable by ligand modifications, that is, varying the ligand spacer bulkiness or substituent position of terminal group. Furthermore, gas adsorption measurements indicate that 4 possesses moderate CO(2) uptake and some adsorption selectivity for CO(2) over N(2).

1D cadmium(II) thiocyanate systems: Synthesis and characterization of three new polymeric 1D cadmium(II) thiocyanato complexes

Abstract Three new cadmium(II) thiocyanato complexes, [{Cd(NCS)2(val)}·H2O]n 1, [Cd(NCS)2(3-ampy)2]n 2, and [Cd(NCS)2(pyrazolinone)]n 3, (val = d , l -valine, 3-ampy = 3-aminopyridine and pyrazolinone = 3-methyl-1-phenyl-2-pyrazolin-5-one) have been synthesized and structurally characterized. The X-ray structure analysis revealed di-μ-N,S thiocyanato bridges connecting cadmium centers in a 1D chain with the co-ligand blocking the remaining coordination sites. The structure of complex 1 features six coordinate Cd(II) centers, each cadmium is surrounded by two N atoms and two S atoms from two bridging N,S-thiocyanato groups giving rise to a zigzag 1D chain and two oxygen atoms of the alternating chelating μ-O,O′-valine that coordinates as zwitterionic terminal amino acid. The structure of complex 2 consists of octahedral Cd(II) centers, connected by di-μ-N,S-bridging NCS groups, thus forming a 1D chain system along the [1 0 1] direction. The amino-groups are forming one intra-chain N H⋯N hydrogen bond and one interchain N H⋯N hydrogen bond to N-atoms of adjacent chains. The structure of 3 reveals di-μ-N,S-NCS doubly bridged unusual penta-coordinated cadmium centers with the alternating monodentate pyrazolinone ligand blocking the fifth coordination site. IR spectra and thermal properties of complexes are reported.

Four 1D and 2D Cadmium(II) Complexes Based on Different Anions and Two Modified Bipyridyl Ligands: Syntheses, Structures, Thermogravimetric, and Fluorescent Properties

AbstractA series of cadmium(II) coordination polymers constructed from 1, 3‐bis(pyridine‐3‐carbonyl)imidazolidin‐2‐thioxo (3‐bpit) and 1, 3‐bis(pyridine‐4‐carbonyl)imidazolidin‐2‐thioxo (4‐bpit), namely,{[Cd(SCN)2(3‐bpit)2]·2(CH3OH)}n (1), {[Cd(NO3)2(3‐bpit)2]·2(CH3OH)}n(2), [CdI2(4‐bpit)]n (3), and [CdCl2(4‐bpit)4]n (4) were prepared and characterized by single‐crystal X‐ray diffraction. Complexes 1 and 2 display different types of infinite 1D helical chain structures, both of which contain 24‐membered metallocyclic rings. Complex 3 is composed of 1D zigzag chains, which further form a 3D supramolecular architecture by weak C–H···S and S···I interactions. Complex 4 also features a 3D supramolecular network assembled from 2D rhombus‐shaped layer through intermolecular hydrogen bonding. These structures indicate that the conformation of the ligand and the diverse anions take important roles in the formation of different frameworks. Thermogravimetric and fluorescent properties over complexes are also discussed.