A (3,9)-connected cadmium 1,2,4-triazolate framework based on a trinuclear inorganic cluster

Hydrothermal reaction of 1,2,4-triazole with CdCl₂?·?2.5H₂O generated a 3-D metal-organic framework, {[Cd₃Cl₂(Trz)₄]?·?H₂O} _n (1) (Trz?=?1,2,4-triazole), which was characterized by elemental analysis, FT-IR, X-ray powder diffraction, X-ray single-crystal diffraction, TG/DTA, and photoluminescence measurements. Compound 1 crystallizes in the orthorhombic system, space group Pnma, a?=?16.906(3)?Å, b?=?8.3151(17)?Å, c?=?13.080(3)?Å, V?=?1838.6(6)?ų, Z?=?4. Cd(1) is coordinated by four nitrogen atoms and one chloride to form a distorted trigonal-bipyramidal geometry. Cd(2) is an octahedron defined by four triazole nitrogen atoms and two chlorides. Two Cd(2) and one Cd(1) are linked by μ ₃-Cl(1) to give a [Cd₃Cl] cluster, which is connected by μ ₂-Cl(2) to generate a 1-D inorganic chain. The 1-D inorganic chains are extended by μ ₃-Trz to form a 2-D hybrid layer in the b, c-plane, which is ultimately linked by residual triazole ligands to give a 3-D framework. The [Cd₃Cl] clusters and the Trz ligands can be regarded as 9- and 3-connected nodes, which lead to an unusual (3,9)-connected net with Schläfli symbol of (4²³?·?6¹³)(4³). The solid 1 exhibits high thermal stability and shows strong blue fluorescence emission at 410?nm in the solid state at ambient temperature.     

Construction of 3,9-diazatetraasteranes and 3,9-diazatetracyclododecanes by photocycloaddition reaction of 1,4-dihydropyridines: Experimental and theoretical investigation

A photocycloaddition reaction of ethyl 1,4-diaryl-1,4-dihydropyridine-3-carboxylate for the construction of 3,9-diazatetraasteranes (P₁) and 3,9-diazatetracyclododecanes (P₂) is reported for the first time. The types of reaction product clearly differ with solvent, regardless of the irradiation wavelength. The difference in P₁ and P₂ lies in the second step of the intramolecular [2 + 2] photocyclization. In order to further investigate this phenomenon and gain a deeper understanding of the photochemical behavior of 1,4-dihydropyridines, DFT and TDDFT theoretical calculations are performed. The results provide a good explanation for the formation of 3,9-diazatetraasteranes and 3,9-diazatetracyclododecanes.     

Mass-spectrometric study of 3,9-diazabicyclo- and 3,9-oxaazabicylo[3.3.1]nonanes

The mass spectra of substituted 3,9-diazabicyclo- and 3,9-oxaazabicyclo[3.3.1]-nonanes were studied as a function of competitive distribution of the charge between the N₃ and N₉ and O₃ and N₉ atoms and the properties of the substituents attached to the heteroatoms. It is shown that a characteristic peculiarity of the fragmentation of 3,9-diazabicyclo[3.3.1]nonanes is fragmentation of the molecular ion with an open structure that is formed by cleavage of the C₁-C₂ bond. The formation of an amine fragment with retention of the bicyclic structure with an exocyclic double bond attached to the quaternary N₉ atom is characteristic for 3,9-oxaazabicyclo[3.3.1]nonanes. It is shown that this sort of behavior of the investigated compounds is determined by their structures and the properties of the heteroatoms in the saturated bicyclic systems.Communication 12 from the series Application of mass spectrometry in structural and stereochemical studies. See [1] for Communication 11.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 229–235, February, 1981.     

Cobalt(III) complexes of 2-oximino-10-oximino-3,9-dimethyl-4,8-diazaundeca-3,8-diene

Summary The pseudo-macrocyclic dioxime ligand [(1) = LH] has been synthesized. A variety of cobalt(III) complexes, trans-[CoLX₂], have been prepared and characterized (X = Cl, Br, NO₂, NCS or N₃) and [CoLCl(NO₂)]. Vis. and i.r. spectra of the complexes are reported and aspects of the solution chemistry of the complexes studied.     

Total synthesis of (3Z,9Z,6S,7R) and (3Z,9Z,6R,7S)-6,7-epoxy-3,9-octadecadienes

(3Z,9Z,6S,7R)-6,7-epoxy-3,9-octadecadiene (1) and (3Z,9Z,6R,7S)-6,7-epoxy-3,9-octadecadiene (2) have been stereoselectively synthesized in eight steps from 2-pentyn-1-ol with an overall yield of 8%. The key steps involved the Sharpless asymmetric dihydroxylation of (2E)-oct-2-en-5-yn-1-ol (6). The new synthetic method is suitable for multigram-scale preparation of 1 and 2 and might be used for producing sufficient quantities of the sex pheromone components for management of the pest of tea plantations.     

OPTICAL ISOMERS OF 2,2′-DIAMINOBIPHENYLBIS(ETHYLENEDIAMINE) COBALT(III) CHLORIDE AND ITS RELATED COMPLEXES1

Abstract

Several cobalt(III) complexes incorporating 2,2′-diaminobiphenyl(dabp) and other 2(2N)- or 4N-type ligands were prepared and resolved by chemical and chromatographic methods: (1) [Co(en)₂(dabp)]Cl₂2H₂O, (2) [Co(l-pn)₂(dabp)] (ClO₄)₃4H₂O, (3) [Co(l-chxn)₂(dabp)](ClO₄)₃3H₂O, (4) α-[Co(trien)(dabp)](ClO₄)₃, (5) α-[Co(2S,9S-dimetrien)(dabp)] (ClO₄)₃ 2H₂O, (6) α-[Co(3S,8S-dimetrien)(dabp)] (ClO₄)₃3H₂O, (7 [Co(tren)(dabp)]Cl₃5H₂O, (8) [Co(bpy)₂(dabp)] Cl₃3H₂O. The complexes (1), (4) and (8) gave one pair of enantiomers, Δ(Λ) and Λ(δ), and the complexes (2) and (3) gave only one Δ-isomer. The absolute configuration of the complexes (5) and (6) was found to be Λ, and that of (7) was not determined because of unsuccessful resolution. The three geometric isomers of the complex (2) were separated and their structures assigned.     

Synthesis,structural studies,and antibacterial activity of zinc,copper, and silver complexes derived from N′-(1-(pyrazin-2-yl)ethylidene)isonicotinohydrazide

The multidentate Schiff-base ligand N′-(1-(pyrazin-2-yl)ethylidene)isonicotinohydrazide (HL) has been prepared. Reaction with zinc, copper, and silver nitrate afford three complexes, [Zn(HL′)₂](NO₃)₂·3H₂O (1), {[Cu₂(L)₂(NO₃)(H₂O)₂]·NO₃}_n (2) and {[Ag₂(L)₂]·3H₂O}_n (3). These complexes have been characterized by elemental analysis, IR spectroscopy, and single-crystal X-ray diffraction. In 1, HL is a neutral tridentate ligand, whereas in 2 and 3, HL is a deprotonated tetradentate ligand. The hydrogen bonding interactions between NO₃^? and the host framework result in various supramolecular polymeric structures: a 2-D layer for 1 and 3-D network for 2 and 3. The antibacterial activities of these complexes have been investigated and the results indicate that 3 showed good antibacterial activities.     

Synthesis,crystal structure,spectroscopy, thermal properties and carbonic anhydrase activities of new metal(II) complexes with mefenamic acid and picoline derivatives

The mononuclear six metal(II) complexes ([Co(mef)₂(3-pic)₂(CH₃OH)₂] (1), [Ni(mef)₂(3-pic)₂(CH₃OH)₂] (2), [Cu(mef)₂(3-pic)₂] (3), [Co(mef)₂(4-pic)₂] (4), [Ni(mef)₂(4-pic)₂] (5), and [Cu(mef)₂(4-pic)₂] (6) with mefenamic acid and picoline ligands were synthesized, characterized, and their carbonic anhydrase inhibitory activities were evaluated. The six complexes were characterized by elemental analysis, FT-IR spectroscopy, and thermal analyses. The crystal structures of 1, 3, and 6 were determined by X-ray crystallography. The complexes have octahedral geometry. In 1, the mefenamato ligand behaved as monodentate whereas in 3 and 6, the mefenamato ligand acted as a bidentate ligand. Complexes 3 and 6 consist of the mefenamate and 4-picoline ligands. In 1, unlike the other complexes, methanol acted as a ligand and was involved in the coordination. Carbonic anhydrase I and II isoenzymes were purified from human erythrocytes. The in vitro effects of mefenamic acid, 3-picoline, 4-picoline, and the six metal(II) complexes on these isoenzymes were evaluated.     

Aqua substitution from mononuclear Pt(II) complexes with 2-(pyrazol-1-ylmethyl)quinoline non-leaving ligands

The rates of aqua substitution from [Pt{2-(pyrazol-1-ylmethyl)quinoline}(H₂O)₂](ClO₄)₂, [Pt(H₂Qn)], [Pt{2-(3,5-dimethylpyrazol-1-ylmethyl)quinoline}(H₂O)₂](ClO₄)₂, [Pt(dCH₃Qn)], [Pt{2-[(3,5-bis(trifluoromethyl)pyrazol-1-ylmethyl]quinoline}(H₂O)₂](ClO₄)₂, [Pt(dCF₃Qn)], and [Pt{2-[(3,5-bis(trifluoromethyl)pyrazol-1-ylmethyl]pyridine}(H₂O)₂](ClO₄)₂, [Pt(dCF₃Py)], with three sulfur donor nucleophiles were studied. The reactions were followed under pseudo-first-order conditions as a function of nucleophile concentration and temperature using a stopped-flow analyzer and UV/visible spectrophotometry. The substitution reactions proceeded sequentially. The second-order rate constants for substituting the aqua ligands in the first substitution step increased in the order Pt(dCH₃Qn) < Pt(dCF₃Qn) < Pt(H₂Qn) < Pt(dCF₃Py), while that of the second substitution step was Pt(dCH₃Qn) < Pt(dCF₃Qn) < Pt(dCF₃Py) < Pt(H₂Qn). The reactivity trends confirm that the quinoline substructure in the (pyrazolylmethyl)quinoline ligands acts as an apparent donor of electron density toward the metal center rather than being a π-acceptor. Measured pK_a values from spectrophotometric acid–base titrations were Pt(H₂Qn) (pK_a1 = 4.56; pK_a2 = 6.32), Pt(dCH₃Qn) (pK_a1 = 4.88; pK_a2 = 6.31), Pt(dCF₃Qn) (pK_a1 = 4.07; pK_a2 = 6.35), and Pt(dCF₃Py) (pK_a1 = 4.76; pK_a2 = 6.27). The activation parameters from the temperature dependence of the second-order rate constants support an associative mechanism of substitution.     

Synthesis and characterization of molybdenum(V,VI) complexes derived from bis(2-hydroxy-1-naphthaldehyde)malonoyldihydrazone

Monometallic molybdenum(VI) complexes [MoO₂(CH₂LH₂)]?·?H₂O (1), [Mo₂O₄(CH₂LH₂)₂(A)₂] (A?=?py (2), 2-pic (3), 3-pic (4) and 4-pic (5)) and molybdenum(V) complexes [Mo(CH₂LH₂)(inh)]?·?H₂O (6) and [Mo(CH₂LH₂)(slh)] (7) of bis(2-hydroxy-1-naphthaldehyde)malonoyldihydrazone (CH₂LH₄) have been synthesized and characterized by various physico-chemical and spectroscopic studies. The compositions of the complexes have been established by elemental analyses and molecular weight determination. The structural assessment of the complexes has been done on the basis of data obtained from molar conductances, magnetic moment studies, electronic, infrared, electron paramagnetic resonance (EPR), proton nuclear magnetic resonance, and ¹³C proton nuclear magnetic resonance spectroscopic studies. The molar conductance values for the complexes in DMSO suggest that they are non-electrolytes. The magnetic moment values for 6 and 7 correspond to one unpaired electron while the remaining complexes are diamagnetic. Complexes 1, 6, and 7 have six-coordinate octahedral stereochemistry around molybdenum, while 2–5 are eight-coordinate dodecahedral around the metal centers. EPR spectral features suggest that 7 is less symmetrical than 6.     

Group III quinaldates: synthesis,structure and photoluminescence

The reactions of Al(III), Ga(III) and In(III) nitrates with 2-quinaldic acid (qaH) afforded [Al₂(OH)₂(qa)₄]·2H₂O (1), [Ga(qa)₂(H₂O)₂]NO₃ (2) and [In(qa)₂(NO₃)(H₂O)] (3), respectively, in high yields. The crystal structures of 1, 2 and 3 have been determined by single-crystal X-ray crystallography. The structure of 1 features a di-hydroxo bridged [Al₂(μ-OH)₂]⁴⁺ dimer in which each Al(III) is further ligated by two bidentate chelate qa^? ligands. Complexes 2 and 3 are mononuclear with the M(III) ions in octahedral environments surrounded by two bidentate chelate qa^? and two H₂O in 2 or one H₂O and a terminal NO₃^? in 3. Characteristic IR as well as thermal analysis and solid-state fluorescence are discussed.     

Dihaloheptasilanes X2Si[SiMe(SiMe3)2]2 as potential precursors for silylenes, disilenes and cyclotrisilanes

The synthesis of new dihaloheptasilanes X₂Si[SiMe(SiMe₃)₂]₂ (X=Cl: 2, Br: 3, I: 4) was performed by treating dihydridoheptasilane 1 (X=H) with CCl₄, HCBr₃ or HCI₃. Difluoroheptasilane 6 (X=F) was prepared from either diphenylheptasilane 5 (X=Ph), triflic acid (HOTf), and LiF with concomitant isolation of heptasilanes 7 (X₂=Ph and OTf), 8 (X₂=F and Ph), and 9 (X₂=F and OTf), or by halogen exchange from 2 using ZnF₂. Crystal structures of 2, 3, 4, and 5 are reported. The reduction of 2 with Li, Na or KC₈ resulted in the instantaneous formation of various cyclotrisilanes, while the reduction of 3 gave exclusively the unsymmetrical cyclotrisilane (E)-1-methyl-2,3,3-tris[methylbis(trimethylsilyl)silyl]-1,2-bis(trimethylsilyl)cyclotrisilane 10, which was characterized by X-ray crystallography. A mechanism for the formation of cyclotrisilanes via a silylsilylene-to-disilene rearrangement is proposed. Attempts to prepare the tetradekasilane [(Me₃Si)₂MeSi]₂SiH–SiH[SiMe(SiMe₃)₂]₂ (by reductive dehalogenation of either HClSi[SiMe(SiMe₃)₂]₂ 13 or HISi[SiMe(SiMe₃)₂]₂ 18), or the tetradekasilane [(Me₃Si)₂MeSi]₂SiPh–SiPh[SiMe(SiMe₃)₂]₂ (by reductive dehalogenation of either PhClSi[SiMe(SiMe₃)₂]₂ 14 or PhISi[SiMe(SiMe₃)₂]₂ 19) as precursors for the disilene [(Me₃Si)₂MeSi]₂Si=Si[SiMe(SiMe₃)₂]₂ failed. 14 was characterized by X-ray crystallography. All compounds described were also characterized by multinuclear NMR spectroscopy and elemental analysis.     

Syntheses,structures, and fluorescent properties of three Zn(II) and Cu(II) complexes of different ligands derived from 3,6-bis(2-pyridyl)-1,2-dihydro-1,2,4,5-tetrazine

Three supramolecular complexes [Zn(HL₁ )₂(H₂O)₂(ZnCl₄)₂] (1), [Cu(L₂ )₂Cl₂] (2), and [Zn(L₃ )Cl₂] (3) have been synthesized and characterized by single crystal X-ray diffraction analysis (L₁ = 3,5-di(2-pyridyl)-4-amino-1,2,4-triazole, L₂ = 3,5-di(2-pyridyl)-1,2,4-triazole, and L₃ = 2-pyridinecarboxylic acid (pyridin-2-ylmethylene)-hydrazide). In 1, anion–π interactions between Cl^? and the π-systems of L₁ are observed and anion–π, hydrogen bonding and π–π stacking interactions link the two complex units of [Zn(HL₁ )₂(H₂O)₂]⁴⁺ and [ZnCl₄]^2? to form a 3-D supramolecular network. In 2, π–π stacking interactions between aromatic rings of 1,2,4-triazole and pyridine rings are observed; in 3, hydrogen bonding of Cl ··· H–N and π–π stacking interactions between parallel pyridine rings of L ₃ are observed. The mechanisms of rearrangement reactions of L to L₁ –L₃ are discussed. The fluorescent properties for solid 1 and 3 are also investigated.     

Synthesis,structure, EPR,and DFT calculation on dinuclear paddle wheel Cu(II) complexes with bis-chelate rings

A series of diester-dicarboxylic acids, L¹H₂, L²H₂, L³H₂, L⁴H₂, and L⁵H₂ and their dinuclear Cu₂ complexes [Cu(L¹)CH₃CN]₂ (1), [Cu(L²)H₂O]₂ (2), [Cu(L³)CH₃CN]₂ (3), [Cu(L⁴)EtOH]₂ (4), and [Cu(L⁵)CH₃CN]₂ (5), were synthesized. The crystal structures obtained for 1, 2, and 4 and the density functional theory optimized structures for 2, 3, and 5 illustrated the formation of tetracarboxylate “paddle wheel” complexes. The phthalyl and diphenyl head groups and the spacer moieties were appropriately altered and the size of the chelate ring expanded from 15-membered in 1 to 21-membered in 5. The dinuclear units have strong Cu–Cu interaction with EPR spectra exploring spin coupled features.     

Binuclear Orthometalated N,N-Dimethylbenzylamine Complexes of Palladium(II): Synthesis,Structures and Thermal Behavior

Abstract

Organochalcogenolate-bridged cyclometalated palladium(II) complexes of the formulae, [Pd₂(μ-Epy)₂(Me₂NCH₂C₆H₄-C,N)₂] (2) (E = S (2a), Se (2b)), [Pd₂(μ-SAr)(μ-Cl)(Me₂NCH₂C₆H₄-C,N)₂] (3) (Ar = Ph (3a), Mes (Mes = 2,4,6-Me₃C₆H₂) (3b)) and [Pd₂(μ-SeAr)₂(Me₂NCH₂C₆H₄-C,N)₂] (4) (Ar = Ph (4a), Mes (4b)), have been synthesized by the reactions of [Pd₂(μ-Cl)₂(Me₂NCH₂C₆H₄-C,N)₂] with lead or sodium salts of the chalcogenolate ligand. These complexes have been characterized by elemental analysis, mass spectral data, and NMR (¹H and ⁷⁷Se{¹H}) spectroscopy. The molecular structure of 2, determined by single crystal X-ray diffraction analysis, revealed a Epy-bridged head-to-tail arrangement in which the eight-membered “(PdECN)₂” ring adopts a distorted twist boat conformation. The Pd····Pd separation in 2a is within the van-der-Waals interaction but in 2b it is too large to support the presence of any metal–metal interaction. The thermal behavior of these complexes has been studied by thermogravimetric analysis.     

NNS tridentate thiosemicarbazide and 1,3,4-thiadiazole-2-amine complexes of some transition metal ions: syntheses,structure and fluorescence properties

The reactions of Zn(II), Mn(II), and Ni(II) acetates with 1-picolinoyl-4-phenyl-3-thiosemicarbazide (Hppts) yielded [Zn(ppts)₂]·CHCl₃ (3), [Mn(ppts)₂]·THF (4), and [Ni(ppts)₂]·THF (5), respectively, but HgCl₂ gave a cyclized product N-phenyl-5-(pyridin-2-yl)-1,3,4-oxadiazole-2-yl-amine (2). The treatment of Hppts with conc. H₂SO₄ formed N-phenyl-5-(pyridin-2-yl)-1,3,4-thiadiazole-2-yl-amine (1). Hppts is a nonfluorescent material, but 3, 4 and the cyclized products 1,3,4-oxadiazole/1,3,4-thiadiazole are fluorescent. The cyclized ligand N-phenyl-5-(pyridin-2-yl)-1,3,4-thiadiazole-2-amine (1) formed [Zn(2-Hppt)₂(OAc)₂] (6) and [Cd₂(2-Hppt)₂(OAc)₂(μ-OAc)₂] (7) in which Cd(II) has a binuclear acetate-bridged seven coordinate pentagonal bipyramidal geometry. Complex 7 is also a fluorescent material with maximum emission at 425 nm at an excitation wavelength of 254 nm.     

Coumarin-naphthohydrazone ligand with a rare coordination mode to form Mn(II) and Co(II) 1-D coordination polymers: synthesis,characterization, and crystal structure

The hydrazone (E)-3-hydroxy-N’-(1-(2-oxo-2H-chromen-3-yl)ethylidene)-2-naphthohydrazide (H₂L) was synthesized from the reaction of 3-acetylcoumarin and 3-hydroxy-2-naphthoic hydrazide in methanol. Compounds [Mn(H₂L)(NO₃)₂(CH₃OH)]·CH₃OH (1a), [Mn(HL)(NO₃)(CH₃OH)]_n (1b), [Co(HL)(NO₃)(CH₃OH)]_n (2), and [Cu(HL)(NO₃)] (3) were obtained by reaction of an equimolar amount of H₂L with nitrate salts of Mn(II), Co(II), or Cu(II) in methanol. The reaction of ligand and Mn(NO₃)₂·4H₂O was also carried out in the presence of sodium azide which led to the 1-D coordination polymer, [Mn(HL)(N₃)(CH₃OH)]_n (4). All of the synthesized compounds were characterized by elemental analyses and spectroscopic methods. Single-crystal X-ray analysis of 1–4 indicated that H₂L is neutral (in 1a) or mononegative ligand (in 1b, 2, 3 and 4). In 1b, 2 and 4 the 1-D polymeric chain is found by a rare coordination mode of this kind of hydrazone ligand since the naphtholic oxygen is coordinated to the neighboring metal ions while the NH moiety of hydrazone remains intact, also confirmed by FT-IR spectroscopic studies. The thermal stability of 2 and 4 were also studied from 30–1000 °C.     

Structures of Mn(II) complexes of bis(2-pyridylmethyl)amine (bpa) and (2-pyridylmethyl)(6-methyl-2-pyridylmethyl)amine (Mebpa): geometric isomerism in the solid state

The crystal structures of [Mn(bpa)₂](ClO₄)₂ (1), [bpa?=?bis(2-pyridylmethyl)amine], and Mn(6-Mebpa)₂(ClO₄)₂ (2), [6-Mebpa?=?(6-methyl-2-pyridylmethyl)(2-pyridylmethyl)amine] have been determined. In 1, two facial [Mn(bpa)₂]²⁺ isomers are observed in the same unit cell, one with C _i (1a) and the other with C₂ (1b) symmetries. In 2, only the isomer with C₂ symmetry is observed. The structure of [Mn(bpa)₂]²⁺ with only C₂ symmetry has been reported previously (Inorg. Chem., 31, 4611 (1992)). The bond length order Mn–N_amine?>?Mn–N_pyridyl, observed in the C₂ and the C _i isomers in the crystals of 1, is the reverse of the order observed in the structure of [Mn(bpa)₂](ClO₄)₂ which contains only the C₂ isomer in the unit cell. The structure of 2 in which only the C₂ isomer is found, also shows the bond length order Mn–N_pyridyl?>?Mn–N_amine. In cyclic voltammetric experiments in acetonitrile solutions, 1 and 2 show irreversible anodic peaks at E _p?=?1.60 and 1.90?V respectively, (vs. Ag/AgCl), assigned to the oxidation of Mn(II) to Mn(III). The substantially higher oxidation potential of 2 is attributable to a higher rearrangement energy in complex 2 due to the steric effect of the methyl substituent.     

3-(2-吡啶基)-1,2,4-三唑配体Co(II)Cu(II)和Cd(II)配合物的合成、结构及荧光性质

利用3-（2-吡啶基）-1,2,4-三唑配体（HL）和不同的金属盐设计合成了5个配合物[Co（HL）₂（H₂O）₂]（NO₃）₂（1）、[Cu₂（L）₂（NO₃）₂（H₂O）₄] （2）、[Cu₂（L）₂（AcO）₂（H₂O）₂]·6H₂O （3）、[Cu₂（L）₂（HL）₂（ClO₄）₂]·2CH₃CN （4）和[Cd₂（L）₂（HL）₂（NO₃）₂]·2H₂O （5）,并通过X射线单晶衍射、红外、元素分析、X射线粉末衍射和热重对配合物结构进行了表征。测试结果表明配合物1具有单核结构,并且可以通过氢键的相互作用形成二维超分子结构。配合物2~5为双核结构。配合物2和5可以通过氢键的相互作用形成二维超分子结构。配合物3通过氢键的相互作用形成三维超分子结构。研究了配合物中HL配体的配位模式。此外,研究了配体HL和配合物1和5的固态荧光性质及荧光寿命。     

Three cobalt coordination polymers based on bis(1,2,4-triazol-1-ylmethyl)benzene positional isomer ligands and thiocyanate

The reaction of three positional isomer ligands of bis(1,2,4-triazol-1-ylmethyl)benzene and Co(NCS)₂ gives three coordination polymers [Co(obtz)₂(NCS)₂] _n (1), [Co(mbtz)₂(NCS)₂] _n (2), and {[Co(bbtz)₂(NCS)₂]?·?2DMF} _n (3). Polymers 1 and 2 are comprised of similar 1-D double chains. In 1, each chain forms π–π stacking interactions with four adjacent chains (two above and two below) to extend to a 3-D supramolecular network. Polymer 3 is a neutral 2-D (4,4) network. The dangling NCS^? inserts into the window of adjacent layers in a mutual relationship and result in a 2-D?→?3-D polythreaded network in 3. The thermal stability and the diffuse reflectance UV-Vis spectroscopy of 1, 2, and 3 were measured.