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This paper describes the synthesis of a new acetylene‐bridged triphosphine, ((phenylphosphanediyl)bis‐(ethyne‐2,1‐diyl))bis(diphenylphosphane) [PhP{C≡CPPh2}2] (2) and its coordination complexes of RuII, RhIII, CuI, PdII and PtII. The reaction of diethynylphenylphosphine [PhP{C≡CH}2] (1) with two equivalents of LiHMDS followed by the addition of PPh2Cl resulted in 2. Treatment of 2 with [Ru(η6‐p‐cymene)Cl2]2 and [RhCp*Cl2]2 in 1 : 1.5 molar ratios produced trinuclear complexes [{Ru(η6‐p‐cymene)Cl2}3{μ3‐PPh(C≡CPPh2)2}] (3) and [(RhCp*Cl2)3{μ3‐PPh(C≡CPPh2)2}] (4). The molecular structure of 3 was confirmed by single crystal X‐ray analysis. Treatment of 2 with M(COD)Cl2 (M=Pd, Pt) in 2 : 3 ratio afforded open book type complexes [(MCl2)3{μ3‐PPh(C≡CPPh2)}2] (5 M=Pd, 6 M=Pt). The reaction of 2 with CuI in 1 : 2 ratio afforded 1‐D coordination polymer [{Cu2(μ2‐I)2(CH3CN)}{PPh(C≡CPPh2)2}3{CuI}2] (7) containing [(CuI)2{μ2‐(P−C≡C−P)3}] cylindrical units. [ABSTRACT FROM AUTHOR]

This paper describes the synthesis of a new acetylene‐bridged triphosphine, ((phenylphosphanediyl)bis‐(ethyne‐2,1‐diyl))bis(diphenylphosphane) [PhP{C≡CPPh2}2] (2) and its coordination complexes of RuII, RhIII, CuI, PdII and PtII. The reaction of diethynylphenylphosphine [PhP{C≡CH}2] (1) with two equivalents of LiHMDS followed by the addition of PPh2Cl resulted in 2. Treatment of 2 with [Ru(η6‐p‐cymene)Cl2]2 and [RhCp*Cl2]2 in 1 : 1.5 molar ratios produced trinuclear complexes [{Ru(η6‐p‐cymene)Cl2}3{μ3‐PPh(C≡CPPh2)2}] (3) and [(RhCp*Cl2)3{μ3‐PPh(C≡CPPh2)2}] (4). The molecular structure of 3 was confirmed by single crystal X‐ray analysis. Treatment of 2 with M(COD)Cl2 (M=Pd, Pt) in 2 : 3 ratio afforded open book type complexes [(MCl2)3{μ3‐PPh(C≡CPPh2)}2] (5 M=Pd, 6 M=Pt). The reaction of 2 with CuI in 1 : 2 ratio afforded 1‐D coordination polymer [{Cu2(μ2‐I)2(CH3CN)}{PPh(C≡CPPh2)2}3{CuI}2] (7) containing [(CuI)2{μ2‐(P−C≡C−P)3}] cylindrical units. [ABSTRACT FROM AUTHOR]

A novel coordination polymer {[Cd4(CPIP)3Cl8]}n (CP1) was constructed from the reaction of CPIP (CPIP=1-chloro-3- (pyridine-2-yl)imidazo[1,5-a]pyridine) and CdCl2⋅2.5H2O under solvothermal conditions. The employment of CPIP as the ligand was based on the consideration that two types of Lewis basic sites (the fused nitrogen atom and the chlorine substituent) are present on the backbone of the ligand. These sites can be utilized for interacting with cations and anions, thus for the sensing functionality. Single-crystal X-ray diffraction studies revealed that CP1 exhibits interesting one-dimensional (1D) polymeric chain structure. The adjacent four CdII ions are connected by one μ3-Cl and five μ2-Cl atoms to form a Chinese-lantern-like topology. CP1 is an excellent luminescent sensor for detecting Cu2+, CrO42- and Cr2O72- ions with high selectivity, sensitivity, and recyclability. Moreover, CP1 is the first reported chloride-bridged coordination polymer that is capable of sensing Cu2+ ion. The mechanisms for sensing Cu2+, CrO42- and Cr2O72- ions were investigated and discussed. [ABSTRACT FROM AUTHOR]

The anionic diamido N‐heterocyclic carbene 1 is used to prepare a series of linear as well as trigonal, heteroleptic CuI complexes with small molecular ligands such as pyridine derivatives or triphenylphosphine. A key role lies in the versatile precursor for these complexes, a moisture‐ and air‐stable 1D coordination polymer [1 ⋅ Cu]n composed of only the NHC ligand and CuI, such that the copper is linearly coordinated by the carbene carbon atom and one oxygen atom of the backbone of the carbene. This polymer can easily be cleaved into monomeric complexes by addition of the desired ligand to dispersions of the polymer in dichloromethane. In solution, the complexes are in equilibrium with this highly insoluble polymer and free ligand. Thus, analytical and spectroscopical experiments with the compounds are limited to their crystalline state, characterized by single crystal X‐ray diffraction experiments. Some of the complexes exhibit visible luminescence in the solid state upon irradiation with ultraviolet light. The spectral features (emission wavelength, Stokes shift, width of the emission band, vibrational fine structure) significantly differ among the complexes. Quantum mechanical computations reveal a subtle interplay of several factors such as coordination number and charge transfer character of the emissive state. [ABSTRACT FROM AUTHOR]

Twenty 3d-4f heterometallic coordination polymers (CPs), namely, [Ln2Co(2,3-pzdc)4(H2O)6]·2H2O [Ln = La (1), Pr (2), Nd (3), Sm (4), Eu (5), Gd (6), Tb (7)], [Ln2Co(2,3-pzdc)4-(H2O)4]·4H2O [Ln = Dy (8), Er (9)], [Ln2Cu(2,3-pzdc)4(H2O)6]·2H2O [Ln = La (10), Pr (11), Nd (12), Sm (13), Eu (14), Gd (15), Tb (16)], [Dy2Cu(2,3-pzdc)4(H2O)4]·4H2O (17), and [Ln2Cu(2,3- pzdc)4(H2O)4]·2H2O [Ln = Er (18), Yb (19), Lu (20)], are synthesized successfully by the reactions of 2,3-H2pzdc with LnCl3·nH2O/Ln(NO3)3·nH2O and Co(NO3)2·3H2O/CuCl2·2H2O under hydrothermal conditions. CPs 1-20 are isostructural, and only the coordination and interstitial water molecules, as well as the coordination numbers of LnIII, are different from each other. In 1-20, the 2,3-pzdc anions link the CoII/CuII and LnIII ions by two coordination modes to form a three-dimensional (3D) framework with a 3,3,4,4-connected (4·62)2(42·62·82)- (6³)2(65·8)2 topology. CPs 6 and 7 manifest the weak ferromagnetic interactions between CoII and LnIII in the low-temperature range. CP 8 exhibits a field-induced slow magnetic relaxation behavior. CP 16 shows a magnetic transition between shortrange ferromagnetic ordering at 60 K and long-range ferromagnetic ordering below 26 K. CP 17 displays field-induced singlemolecule magnet (SMM) behavior, with a Ueff value of 102.4 K. [ABSTRACT FROM AUTHOR]

By designing and using a new flexible bis(pyrimidine)‐bis(amide) ligand H2L [H2L=N,N′‐bis(4‐pyrimidinecarboxamido)‐1,3‐propane], two new polyoxometalate (POM)‐based metal‐organic complexes (MOCs), H3[Cu2(L)2(PMo12O40)] (1) and [Cu2(H2L)2(β‐Mo8O26)] (2), were synthesized under solvothermal and hydrothermal conditions, respectively. In complexes 1 and 2, metal‐organic units and POM anions are linked together to form two distinct 2D structures. The [PMo12O40]3− (PMo12) anions were used as μ4‐bridging ligands in complex 1 and linked the 1D [Cu(L)]n metal‐organic chains to form a 2D layered structure. The [β‐Mo8O26]4− (Mo8) anions adopted two diverse coordination modes in complex 2 and connected the 1D [Cu(H2L)]n2n+ metal‐organic chains to generate a 2D grid structure. Complexes 1–2 can serve as electrode materials of supercapacitor and show large specific capacitances, up to 1065 and 956 F g−1 at current density of 2 A g−1, respectively, which surpass the parent POM and most of the previous reported POM‐based electrode materials, thus demonstrating the important role of introducing metal‐organic units in improving capacitive performances. Besides, the electrocatalytic redox activities of complexes 1–2 were also studied, both of them can be used as electrochemical sensors to detect Cr(VI) ions. They possess high sensitivity of 0.537 and 0.455 μA μM−1 and low detection limits of 0.16 and 0.33 μM, which are below the maximum content of Cr(VI) in groundwater required by the WHO. [ABSTRACT FROM AUTHOR]

The tetradentate organotelluroether (C9H6NTe)2CH2 ligand has been synthesized and its coordination behaviour with a stoichiometric amount of copper(II) and silver(I) perchlorate and triflate salts has been experimentally investigated. The isolated ligand and metal complexes are characterized by multinuclear (1H, 13C, 125Te) NMR spectroscopy, single crystal X‐ray diffraction, and DFT calculations. The X‐ray analysis revealed the formation of self‐assembled bimetallic complexes with the molecular formula of 2[M(C9H6NTe)2CH2]+ X− [M+=Cu, Ag; X−=ClO4, CF3SO3]. Further, it has been noticed that the metal ions act as a bridging unit to form cationic 8‐membered metallamacrocycles in the chair conformation. The atoms in molecule (AIM) and non‐covalent interactions (NCI) analysis display a weak intramolecular Te⋅⋅⋅Te interaction. Natural bond orbital (NBO) calculations suggest that the tellurium has a rich electron donating ability toward metal ions than the quinoline nitrogen in the complexes. [ABSTRACT FROM AUTHOR]

Employment of N,N′‐bis(2‐hydroxy‐4‐carboxyphenyl)oxalamide (H6L) in Cu2+ chemistry afforded the mononuclear complex (Et4N)4[CuL] ⋅ 13H2O (A) which comprises a square planar [CuL]4− complex with several O donor atoms in its periphery. The 1 : 1 reaction between complex A and Ln(NO3)3 ⋅ xH2O (Ln=La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er and Yb, x=6 or 9) in 1 : 4 mixture of ethanol/water in the presence of excess of KCl yielded two families of isomorphous 3d/4f coordination polymers, namely (Et4N)0.5[K0.5(H2O)Ln(H2O)4(CuL)] ⋅ 3H2O [Ln=La(1), Ce(2), Pr(3), Nd(4), Sm(5), Eu(6) and Gd(7)] and [K(H2O)Ln(H2O)4(CuL)] ⋅ ⋅6H2O [Ln=Tb(8), Dy(9), Ho(10), Er(11) and Yb(12)]. The crystal structures of 2–4 revealed the presence of 3D coordination polymers while the crystal structure of 9 the presence of a 2D coordination polymer. In both 3d/4f families, complex A retains its original structure and serves as a "metallo‐ligand". The magnetic properties of 2–4, 7–9, 11 and 12 are discussed. [ABSTRACT FROM AUTHOR]

The equal molar reaction of Cu(BF4)2 ·3H2O with the ditopic, bis(pyrazolyl)methane ligand p-[CH(pz)2]2C6H4 ( L p) where pz is a pyrazolyl ring, in methanol produces [Cu(μ- L p)(CH3OH)](BF4)2 ·(CH3OH)0.62 ( 1) and a similar reaction in water/methanol yields [Cu(μ- L p)(CH3OH)]2(SiF6)(BF4)2 ·(CH3OH)2 ( 2). The water/ethanol solvent system yields both [Cu2(μ- L p)(H2O)6](SiF6)2 ·(H2O)4 ( 3) and [Cu(μ- L p)(H2O)](BF4)2 ·(CH3CH2OH)2 ( 4), and if the ratio of Cu(BF4)2 ·3H2O and L p is changed to 2:1, only 3 forms. Recrystallization of the solid formed from the reaction of THF solutions of Cu(BF4)2 ·3H2O with L p from DMSO yields [Cu2(μ- L p)(DMSO)6](BF4)4 ·(DMSO)2 ·C6H6 ·(H2O)0.5 ( 5) and a recrystallization of compound 1 from DMSO yields [Cu2(μ- L p)(DMSO)6](BF4)4 ·(DMSO)2 ·C6H6 ( 6). Complexes 1, 2, and 4 are coordination polymers in which the N4O-coordinated, square-pyramidal copper(II) ions are oriented in an anti conformation withrespect to the phenylene spacer of L p. Complexes 3, 5 and 6 are dinuclear with N2O3-coordinated, square-pyramidal copper(II) ions again oriented in an anti configuration with respect to the bridging L p. The square pyramidal geometries show axial elongation, a result of pseudo Jahn-Teller electronic effects. In the cases of the coordination polymers, the axially coordinated solvent molecule is lost at low temperatures upon heating of the crystals. The three compounds in each structural type have nearly the same overall configurations. Cooperative effects of O-H ···F, O-H ···O and C-H ···F hydrogen bonding interactions organize the supramolecular structures and influence the crystal packing of complexes 1- 4. The C-H ···F interactions have metrics that indicate they are unusually strong, due to the enhanced polarization of the C-H bond and charge assistance from the anionic fluorine atom. [ABSTRACT FROM AUTHOR]

We report magnetic, EPR, and computational studies on two representative examples of structurally well‐characterized one dimension (1D) molecular systems: the copper complexes catena‐[bis(μ‐pyridine‐2‐carboxylato)‐copper dihydrate] and catena‐[(μ2‐pyridine‐2,6‐dicarboxylato)‐diaqua‐copper(II)], hereafter 1 and 2, respectively. Experimental and theoretical results confirmed that the structural chains in both compounds behave as magnetic chains in which the copper ions are weakly coupled by isotropic exchange. Magnetic susceptibility measurements of 1 suggested that the copper ions are antiferromagnetically coupled whereas EPR measurements suggested ferromagnetic coupling at temperature above 100 K which becomes antiferromagnetic at low temperatures. Computational calculations would indicate that the ferromagnetic‐antiferromagnetic change may be due to dCu−Oap shortening on lowering temperature temperature (a fact that was observed experimentally by XRD at low temperatures), which redistributes the small Cu(II) unpaired spin density delocalized on the apical ligand to copper. The 1D magnetic behavior of the zigzag ladder chain of 2 is less detectable than that of the single chain of 1. Magnetic susceptibility measurements in conjunction with computational calculations showed that the pathways that give rise to the 1D ladder transmit ferromagnetic exchange interactions with different strengths, with the stronger interaction being transmitted along the rungs. The role of the weaker exchange interactions transmitted along the rails on the magnetic dimensionality of 2 is analyzed. [ABSTRACT FROM AUTHOR]

The new Cu(I) complex [Cu(PNPNTPh‐Ph)Cl] (1) containing the tridentate PNP pincer ligand N,N′‐bis(diphenylphosphino)‐2,6‐diamino‐4‐phenyl‐1,3,5‐triazine was obtained from the reaction of [Cu(SMe2)Cl]n with the ligand as ether solvate 1.0.5Et2O. 1 was independently obtained from a reaction mixture containing the ligand and the Cu(II) precursor CuCl2.2H2O in 50 % yield alongside with the Cu(II) coordination polymer [Cu(O2PPh2)2]n (2). From the reaction of Cu(NO3)2 ⋅ 3H2O with PNPNTPh‐Ph in the presence of pyridine the complexes [Cu(O2PPh2)2(Py)2(H2O)] (3), [Cu(O2PPh2)(Py)2(NO3)]2 (4), and [Cu(Py)4(NO3)2].Py (5), were obtained, 2, 3, and 4 contain diphenyl‐phosphinate ligands. The underlying redox reaction of the ligand and Cu(II) yielding the oxidised ligands observed in the by‐products and the Cu(I) product complex was further studied using electrochemistry and UV‐vis spectroelectrochemistry. Attempts to synthesise the Cu(II) complex [Cu(PNPNTPh‐Ph)(NO3)2] (6) in a mechanochemical experiment gave evidence for this unprecedented species from ESI‐MS(+) and EPR spectroscopy but also revealed its very high sensitivity to air and moisture. The catalytic activity of 1 was investigated in the azide‐alkyne cycloaddition yielding various 1‐benzyl‐4‐phenyl‐1H‐1,2,3‐triazoles. The environmentally benign ("green") and cheap EtOH/H2O solvent mixture turned out to be very suitable. Melting points, FT‐IR, and NMR spectra of the triazole products were analysed. [ABSTRACT FROM AUTHOR]

Five coordination compounds [Cu2(impc)2(µ2‐OH)Cl]n (1), [Cu2(impc)2(µ2‐OH)Br]n (2), [Co(impc)2(H2O)2]n (3), [Co4(impc)4(SO4)2(H2O)]n (4) and {[Co(impc)(H2O)2]·H2O} (5) based on asymmetric 5‐(1H‐imidazole‐1‐yl)‐3‐pyridinecarboxylic acid (Himpc) have been hydrothermally synthesized and structurally characterized. 1 and 2 are isostructural and consist of binuclear CuII units and display two‐dimensional (2D) framework, where 1 and 2 present a new {(4.62)(42.65.82.10)(4)} topology. 3 features a 1D chain structure. Polymer 4, which also displays a new Schläfli symbol {(413.620.88.104)(43)2(4)}, contains tetranuclear CoII cluster and is a 2D structure. The planar‐type tetranuclear CoII cluster with SO42– bridge in 4 has not been reported. Compound 5 possesses a mononuclear structure. Magnetic susceptibility studies for 1 and 2 with Cu2 units reveal the antiferromagnetic coupling with J = –3.42 cm–1 for 1 and J = –3.83 cm–1 for 2. Contrary to the only example of class F2 ferromagnetic VII, 1 and 2 (class F2) exhibit different antiferromagnetic behavior. Compounds 3 and 5 exhibit ferromagnetic behavior, and their M(H) curve is consistent with the ferromagnetic nature. No peaks are observed in the out‐of‐phase (χ'') plots of 3, suggesting no long‐range order and no spin canting. For 4 with the Co4 units, it also exhibits ferromagnetic behavior, and the M(H) curve is consistent with the ferromagnetic nature. [ABSTRACT FROM AUTHOR]

Synthesis, and copper(I) and gold(I) complexes of imidazole‐based bisphosphine, [2,6‐(PPh2C3H2N2)2C5H3N] are described. Reactions of [2,6‐(PPh2C3H2N2)2C5H3N] with one equivalent of CuX (X = Cl, Br or I) yielded either monomeric [{2,6‐{PPh2C3H2N2}2C5H3N}{CuI}], dimeric [{PPh2C3H2N2}2C5H3N}{CuCl}]2, or one‐dimensional (1D) polymeric [{2,6‐(PPh2‐C3H2N2)2C5H3N}{Cu3Br2}]nCl complexes. Coordination polymer [{2,6‐(PPh2C3H2N2)2C5H3N}{Cu3Br2}]nCl is a rare example containing alternately arranged copper atoms having tetrahedral and linear geometries. The repeating unit consists of imidazolyl nitrogen atoms from two ligands bind to a copper atom in a linear fashion, whereas two phosphorus atoms from the same ligand are chelated to a tetrahedral copper atom, thus ligand displaying tetradentate behavior. Treatment of bisphosphine with two equivalents of [AuCl(SMe2)] yielded digold complex [2,6‐(PPh2C3H2N2)2C5H3N{AuCl}2]. The structures of most of these compounds were confirmed by single‐crystal X‐ray analyses. These complexes show good photoluminescence properties as well. [ABSTRACT FROM AUTHOR]

The results discussed herein reinforce the relevance of the hydrothermal recrystallization in transition metal hexacyanometallates as a suitable strategy to access the structural diversity of this family of coordination polymers. Copper(2+) and nickel(2+) hexacyanoosmates(II) were prepared by the precipitation method using hexacyanoosmic(II) acid as the complex anion source, obtaining powders of insufficient crystalline quality for the structural study. These powders were then recrystallized under hydrothermal conditions. For Ni, three new phases where formed, monoclinic and tetragonal, and a hexagonal modification when the monoclinic one is dehydrated under soft heating. For copper, one new tetragonal phase was found, in addition to the previously reported cubic one, typical of Prussian blue analogues. The crystal structure for these four nickel and cooper hexacyanoosmates(II) were solved and refined ab initio from powder XRD data. The refined crystal structures are properly supported by a detailed spectroscopic study from IR and UV/Vis data, Ligand Field Analysis, and thermal, magnetic and hydrogen adsorption measurements. In the anhydrous phase for nickel, neighboring Ni atoms were found coordinated by bifurcated N end, an atypical coordination mode for the CN– ligand. The results herein discussed contribute to shed light on the vast information unrevealed on the coordination chemistry of transition metal hexacyanometallates. [ABSTRACT FROM AUTHOR]

Trianionic ligands with an inner N2O2, an outer O2O2 or O2O coordination site and an oxygen atom coming from an amide function not involved in these sites yield dinuclear Cu‐Ln complexes that self‐assemble into tetranuclear species with an alternate arrangement of Cu and Ln ions. This alternate Cu‐Gd arrangement impedes Cu–Cu and Gd‐Gd interactions that could be antiferromagnetic and favours ferromagnetic Cu‐Gd interactions whose strength depends on the nature of the bridge, the phenoxo bridge made of a single oxygen atom or the amidato bridge made of three NCO atoms. Depending on the ligands, the phenoxo bridges can be single (CuOGd) or double (CuO2Gd), while the amidato bridge is always a single (CuNCOGd) bridge. A particular complex involving a trinuclear Cu‐Gd‐Cu arrangement through two amidato bridges confirms that the Cu‐Gd interaction through the amidato bridge is always weaker than the interaction through the phenoxo bridge. It has been possible to obtain complexes with an alternate Cu‐Gd arrangement involving more than two Cu‐Gd entities when two amidato bridges are present. These two amidato bridges may come from a main ligand, as in the case of tetraanionic ligands possessing two amide functions, or from two different ligands involving one amide function that are assembled by a Gd ion through their phenoxo functions. Note that the presence of auxiliary ligands with a good chelating ability for the Gd ion, such as the diketonato ligands, allows isolation of tetranuclear species only, regardless of the number of amide functions. [ABSTRACT FROM AUTHOR]

The charge redistribution effects determine the physical and functional properties of transition metal hexacyanometallates. The π‐back bonding interaction between the CN ligand and the metal (M) linked at its C end and the σ donation from the N end to a second transition metal (T), when a coordination polymer is formed, are relevant features of such effects. The π‐back donation interaction contributes to the overlapping of the electron clouds of M and T metals in the ···–T–N≡C–M–C≡N–T‐··· chain. In this contribution, we demonstrate that XPS spectroscopy is a useful tool to sense the change in the electron density redistribution in hexacyanometallates related to these two mechanisms. The results herein discussed contribute to understand the physical and chemical properties of these materials. Initially, a series of potassium salts, Kn[M6–n(CN)6] (M = CrIII, FeII, RuII, OsII, CoIII, RhIII, IrIII, PtIV) is considered in order to evaluate the role of the π‐back donation on the electron density found at the N atom, which determines the strength for the T‐NC coordination bond and of the mentioned electron clouds overlapping. Then, a representative set of transition metal (T) hexacyanometallates, T2(1‐y)K2y[FeII(CN)6], is studied in order to shed light on the electron density redistribution when a coordination bond is formed at the N end. Within such coordination polymers, the copper (2+) salts are particularly attractive by the unique interaction between the copper atom and the hexacyanometallate ion, and the potential applications of these copper (2+) complexes in heterogeneous catalysis and other areas. From these reasons, the recorded XPS spectra for Cu (2+) hexacyanometallates were evaluated in detail. In accordance with a previous study of these copper (2+) coordination polymers using other techniques, XPS data is sensing an atypical strong bonding interaction with the CN ligand. The experimental XPS data herein discussed are relevant for the coordination chemistry of transition metal hexacyanometallates and for the research community involved in their applications. [ABSTRACT FROM AUTHOR]

The reaction of a non‐symmetrical pyridine‐NHC‐phosphane (NĈP) ligand – generated in situ upon the deprotonation of the corresponding imidazolium salt – with equimolar amount of [Cu(NCMe)4](BF4) or Mn2(CO)10 leads to the formation of bimetallic complexes [Cu2(NĈP)2(NCMe)](BF4)2 and [Mn2(CO)7(NĈP)], respectively, in which the tridentate ligand exhibits an unusual µ‐κ2Ĉ,N‐M;κ1P‐M coordination mode. According to NMR spectroscopy and mass spectrometry, the binuclear copper complex is in equilibrium in MeCN solution with two mononuclear species, namely [Cu(κ2Ĉ,P‐NĈP)2](BF4) and [Cu(κ3‐N,Ĉ,P‐NĈP)(NCMe)](BF4). [ABSTRACT FROM AUTHOR]

For the first time, the tetrahedral diphosphorus complex [Cp2W2(CO)4(µ,η2:η2‐P2)] (Cp = C5H5) (3) is used as a connecter in supramolecular chemistry. The treatment of 3 with CuI halides leads to the formation of the new one‐dimensional (1D) linear polymers [Cu(µ‐X){Cp2W2(CO)4(µ,η2:η2:η1:η1‐P2)}]n {X = Cl (4), Br (5), I (6)}. The coordination polymers (CPs) 4–6 are almost insoluble in organic solvents, thus, their 31P MAS‐NMR spectra were recorded and found to be remarkably influenced by their solid‐state structures. Additionally, we demonstrate that by reacting the Cp‐substituted diphosphorus complex [Cp′2W2(CO)4(µ,η2:η2‐P2)] {Cp′ = C5H4{C(CH3)3}} (7) with CuBr, the unprecedented soluble 1D CP [Cu(µ‐Br){Cp′2W2(CO)4(µ,η2:η2:η1:η1‐P2)}]n (8) is obtained. Furthermore, the reactions of 3 with the AgI salts Ag[CF3SO3] and Ag[PF6] result in the formation of the oligomeric dicationic species [Ag2{Cp2W2(CO)4(µ,η2:η2:η2‐P2)}2 {Cp2W2(CO)4(µ,η2:η2:η1:η1‐P2)}2][X′]2 {X′ = [CF3SO3]– (9), [PF6]– (10)}. [ABSTRACT FROM AUTHOR]

Reactive bubbly flows are at the heart of multiphase flows which are a major topic in chemical engineering since many bulk chemicals are produced in bubbly flows. However, the factors determining product yield and selectivity are often subject of complicated mass transfer effects. Herein, we describe the latest developments in the detection of mass transfer effects in bubbly flows. Coordination chemistry has given new impulses to this topic due to the possibility to synthesise tailored complex systems for the detection of O2 and NO with various time‐ and space‐resolved techniques. For each chemical reaction system, a background section is summarised to allow the reader to get an overview of the different systems. [ABSTRACT FROM AUTHOR]

The reaction of a compartmental ligand N,N′‐bis(3‐methoxysalicylidene)‐1,3‐diamino‐2‐propanol (LH3) with CuII and LnIII salts under solvothermal conditions afforded two‐dimensional coordination polymers, [{Cu5Gd2(L)2(µ3‐OH)4(NO3)4(µ‐OH2)2}(NO3)2]∞ (1) and [{Cu5Dy2(L)2(µ3‐OH)4(NO3)4(MeOH)2}(NO3)2]∞ (2). A detailed study of the magnetic properties of the two coordination polymers reveals that the [Cu5Dy2] analogue shows single‐molecule magnet (SMM) behavior with an energy barrier of about 12 K with τ0 = 10–6 s under zero‐dc field, while the [Cu5Gd2] analogue shows magnetocaloric effect with a –ΔSm value of 17.55 J kg–1 K–1 at T = 2 K (ΔB = 5 T). Interestingly, the magnetic and SMM properties of the previously reported molecular and one‐dimensional analogues containing the [Cu5Ln2] motif are preserved even in the two‐dimensional coordination networks. [ABSTRACT FROM AUTHOR]

Four new three-dimensional heterometallic coordination polymers (CPs), [{Zn3(Hen)(OH)}{Cu6(6-mna)6}·(H2O)6] (I), [{Zn2(OH)(en)}{Cu6(6-mna)6}0.5·(H2O)2·EtOH] (II), [{Zn3(dap)3- (H2O)}{Cu6(6-mna)6}·(H2O)4] (III), and [{Zn2(4,4'-bpy)0.5(OH)- (H2O)}{Cu6(6-mna)6}0.5·(H2O)] (IV) (en = ethylenediamine, 6- H2mna = 6-mercaptonicotinic acid, dap = 1,2-diaminopropane, 4,4'-bpy = 4,4'-bipyridine), have been synthesized and their structures determined by single-crystal X-ray crystallography. The compounds consist of Cu6S6 octahedral clusters linked through the carboxylates to different zinc-oxo clusters. Thus, the compounds contain CuI- and ZnII-based clusters, which are not commonly observed in coordination polymer structures. Compound I stabilizes in a NiAs-related structure, compounds II and IV in a NaCl-related structure, and compound III is a new type of network structure. All the compounds were active catalysts in the heterogeneous nitroaldol reaction. [ABSTRACT FROM AUTHOR]

As a contribution to a better understanding of the coordination properties of imidazolinium-dithiocarboxylate ligands towards copper, the first route towards oligonuclear copper-betaine complexes has been developed. Treatment of the coordination polymer [CuCl(Bz2ImCS2)]n (1) suspended in aceto-nitrile with thallium(I) hexafluorophosphate in different ratios affords the discrete copper(I) cluster cations [Cu4(Bz2ImCS2)4-Cl2]2+ (2) and [Cu3(Bz2ImCS2)5]3+ (3). Single-crystal X-ray diffraction of 2(PF6)2·2MeCN and 3(PF6)3·2MeCN·Et2O reveals the occurrence of unique copper-sulfur architectures. The Cu-S/Cl skeleton of 2 contains two elongated trigonal-prismatic {Cu4S2} entities which share a common {Cu4} face. In contrast, the Cu atoms of 3 define an isosceles triangle. Both compounds exhibit distorted tetrahedral copper coordination sites, based on S3Cl (within 2) and S4 (within 3) donor sets, and host dithiocarboxylate zwitterions in each of two different coordination modes. Overall, three different types of binding principles towards copper are presented here. [ABSTRACT FROM AUTHOR]

Three new copper azide compounds, [Cu5(N3)10-(N-2AE-1,3-DAP)2] (I), [Cu5(N3)10(N-3AP-1,3-DAP)2] (II), and [Cu7(N3)16(1-(2-AE)PIP-H)2] (III) {where N-2AE-1,3-DAP = N-2-aminoethyl-1,3-propanediamine, N-3AP-1,3-DAP = N-3-amino-propyl-1,3-propanediamine, and 1-(2-AE)PIP = 1-(2-amino-ethyl)piperazine} have been prepared by employing aliphatic amine molecules as coordination blocking amines. All the structures are built up by copper azide units linked through a copper–amine metalloligand, forming two-dimensional layers. Compounds I and II have linear copper azide chains, whereas compound III has Cu5 linear units. The structures of I and II are identical except for the blocking amine molecule. The blocking amine molecule in III is protonated, which is rarely observed. Magnetic studies indicate antiferromagnetic behavior with possible metamagnet-like features in all the compounds. [ABSTRACT FROM AUTHOR]

From a new rigid N-donor ligand, 3,6-di(1 H-imidazol-1-yl)-9 H-carbazole ( L), two coordination polymers (CPs) formulated as Cd L( L1) ·3DMF ( 1; H2 L1 = 4,4′-carbonyldibenzoic acid, DMF = N, N-dimethylformamide) and Cu2 L2(SO4) ( 2) were synthesized solvothermally and structurally characterized by single-crystal X-ray diffraction. CP 1 exhibits a two-dimensional (2D) structure, and CP 2 shows one-dimensional (1D) chains. The two CPs exhibit different quasireversible redox properties and possess very weak photoluminescence properties. Density functional theory (DFT) calculations and experimental results show that CP 1 has a wider band gap than that of CP 2. Notably, CP 2 produces a higher photocurrent density than that of CP 1 upon visible-light illumination, which is also in agreement with their Nyquist plots and Mott-Schottky curves. Thin-film CP 1 was obtained by physical exfoliation in methanol and shows more active electrochemical behavior and enhanced photoresponse relative to those of bulk CP 1. [ABSTRACT FROM AUTHOR]

Herein, we report the characterization of a series of CuCN-based coordination polymers that display different crystal packing and electronic properties, namely, [Na2Cu(CN)3 ·3H2O] n ( 1), [Cu4(CN)5(NH3)2(H2O)] n ( 2), [Cu3(CN)4(NH3)3] n ( 3), [Cu3(CN)3(O)0.25(NH3)] n ( 4), [Cu5(CN)6(NH3)4] n ( 5), and [Cu5(CN)6(NH3)2] n ( 6). Spectroscopic evidence of the presence of ammonia molecules coordinated to the metal centers is provided, in particular for 4, which is a new structure. The characterization has been performed by single-crystal XRD (SCXRD), micro- IR spectroscopy, micro-Raman spectroscopy, differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). The photophysical properties have been studied through solid-state luminescence spectroscopy by acquiring the emission and excitation spectra and evaluating the emission quantum yields, which is an approach that has recently grown in importance in the solid-state field. The goals of this work are (1) to elucidate the correlation between the luminescence properties and the presence of either CuI or mixed CuI/CuII oxidation states, (2) to evaluate the presence of NH3, H2O, or both in the polymers through a combined crystallographic-spectroscopic study, and (3) to rationalize the supramolecular architecture and its influence on the resulting luminescence. [ABSTRACT FROM AUTHOR]

A series of copper-lanthanide heterometallic coordination polymers (CPs), [LnCu(2,3-pydc)2(suc)0.5(H2O)3] ·H2O [Ln = La ( 1), Pr ( 2), Nd ( 3), Sm ( 4), Gd ( 5), and Eu ( 6), 2,3-H2pydc = pyridine-2,3-dicarboxylic acid, H2suc = succinic acid], [Ln2Cu3(2,3-pydc)6(H2O)10] ·8H2O [Ln = Eu ( 7), Tb ( 8), Dy ( 9), and Er ( 10)], and [Ln2Cu(2,3-pydc)2(suc)(µ2-OH)2(H2O)2] ·2H2O [Ln = Er ( 11), Yb ( 12), and Lu ( 13)], were synthesized by the hydrothermal reactions of LnCl3 · nH2O, Cu(NO3)2 ·3H2O, pyridine-2,3-dicarboxylic acid (2,3-H2pydc), and N, N′-di(4 H-1,2,4-triazole)butanamide (dtb). CPs 1- 13 possess three types of three-dimensional (3D) frameworks. In 1- 6, the dinuclear Cu2(2,3-pydc)4 and Ln2(COO)2 units link to each other to form two-dimensional (2D) layers, which are extended by the suc anions into a 3D framework. In 7- 10, the lanthanide ions connect the trinuclear Cu3(2,3-pydc)6 units into a 3D framework. In 11- 13, the mononuclear Cu(2,3-pydc)2 units bridge the one-dimensional (1D) lanthanide chains into 2D layers, which are linked by the suc anions into a 3D framework. CP 9 shows a field-induced slow magnetic relaxation behavior with a Ueff value of 83.7 K. [ABSTRACT FROM AUTHOR]

Phosphaferrocenes in combination with coinage metal salts proved to be excellent building blocks in supramolecular chemistry for the buildup of oligomeric and polymeric assemblies. The synthesis of a series of novel phosphaferrocenes containing the 1,3-P2C3 iPr3 and/or the 1,2,4-P3C2 iPr2 ligand is described herein. The self-assembly processes of the 1,3-diphospha-, 1,2,4-triphospha-, and 1,1′,2,3′,4-pentaphosphaferrocenes with CuI halides led to the formation of 1D or 2D polymers. With [Cp*Fe(η5-P2C3 iPr3)] (Cp* = η5-C5Me5), infinite chains are formed, whereas with [(η5-P3C2 iPr2)Fe(η5-P2C3 iPr3)] 1D ladderlike structures are obtained. These are the first polymers containing such a di- and pentaphosphaferrocene, respectively. On the other hand, the use of [Cp*Fe(η5-P3C2 iPr2)] leads to the construction of 2D networks with intact sandwich complexes, which is uncommon for this class of complexes. [ABSTRACT FROM AUTHOR]

The synthesis, characterization, and thermal decomposition behaviour of the oxalato-bridged copper(II) coordination polymer [Cu2(C2O4)(L)2Cl2(MeOH)2] n ( 1) (L = 3,5-dimethyl-1 H-pyrazole) is reported. Complex 1 is prepared in a straightforward fashion by a one-pot reaction of acetylacetone, thiosemicarbazide, oxalic acid and copper(II) chloride in a molar ratio of 2:2:1:2. Complex 1 was characterized by means of FT-IR spectroscopy, mass spectrometry and elemental analysis as well as single-crystal X-ray diffraction. Furthermore, the electrochemical behavior of 1 was investigated in DMSO by cyclic voltammetry. The thermal stability of complex 1 was studied by thermal gravimetric (TG) and differential thermal analyses (DTA). Solventless thermolysis of complex 1 at 550 °C and 1000 °C under air afforded copper oxide nanoparticles and nanosheets, respectively. The CuO nanostructures were characterized by using a series of techniques including FT-IR, UV/Vis, XRD, XPS, EDAX, and SEM. [ABSTRACT FROM AUTHOR]

The reactions of CuSO4 ·5H2O and Ba(R2mal) [R2mal2- is the dianion of 1,1-cyclopropanedicarboxylic acid (H2Cpdc), 1,1-cyclobutanedicarboxylic acid (H2Cbdc), or butylmalonic (H2Bumal) acid] in water give crystals of the 3D coordination polymers [BaCu(Cpdc)2] n ( 1), [BaCu(Cbdc)2(H2O)] n ( 2) and [Ba3Cu3(Bumal)6(H2O)11] n ·2 n(H2O) ( 3). The heating of 2 in air to 200 °C for 60 min results in the removal of the coordinated water molecules to give anhydrous [BaCu(Cbdc)2] n ( 4). The structures of 1- 3 were determined by single-crystal XRD, and that of 4 was derived from powder XRD (XPRD) data. It was assumed that the crystal structures of the polymer complexes that we isolated were determined, to a considerable extent, by the nature of the substituent of the dicarboxylic acid. For 2, the dicarboxylic acid contains closed cyclic moieties, which are retained during dehydration to give 4. A comparative study of the thermal decomposition processes and thermal kinetics of 1- 3 showed that the dehydration proceeds by a single scheme, and the bonds between the structural moieties in the anhydrous intermediates become stronger. The thermal destruction of the anhydrous compounds 1, 4 and { 3} [the dehydrated intermediate of the thermal decomposition of 3, as proved by thermogravimetric analysis (TGA) data] occurs above 170 °C. The phase compositions of their solid products are determined by the thermolysis conditions, and the formation of BaCuO2 from 3 can be realized under milder conditions than those for the formation from 1 and 2. [ABSTRACT FROM AUTHOR]

A new bis(pyrazolecarboxylate) ligand, 1,3-phenylenebis(1 H-pyrazole-5-carboxylic acid) (H2PBPC) has been synthesized to study the structure and intriguing properties of the resultant coordination polymers synthesized under solvothermal conditions. The reaction of H2PBPC with Cu(ClO4)2 in the presence of NaOH at two different temperatures (80 and 120 °C) resulted in two coordination polymers, namely, [{Cu2Na(H2OPBPC)}]∞ ( 1) and [{Cu4Na2(H2OPBPC)2}]∞ ( 2), which display 2D corrugated sheet and 3D staircase architectures, respectively; in these structures, the aromatic C-H bond flanked by the pyrazolecarboxylate moieties was oxidized to form a C-O bond. When 2,2′-bipyridine (2,2′-bpy) was used instead of NaOH, [{Cu2(2,2′-bpy)2(H2PBPC)}(H2O)]∞ ( 3) formed, and such C-H bond activation was not observed. Interestingly, one of the coordination polymers, namely, 1, displayed catecholase and phosphatase activity. Variable-temperature magnetic susceptibility data in the range 2-300 K showed that there is antiferromagnetic coupling between the metal centers of 1 and 2 that is mediated through the phenoxo and pyrazole bridges, whereas 3 revealed dominant ferromagnetic interactions between the bis(pyrazolato)-bridged CuII centers owing to its very unusual Cu-N-N-Cu torsion angles of 75.28 and 69.52°. [ABSTRACT FROM AUTHOR]

As a heterofunctional pro-ligand with both hard and soft coordination sites, trans-3-(3-pyridyl)acrylic acid (LH) is of potential interest for the design of heterometallic complexes of f- and d-block cations, as previously shown in the case of lanthanides. The reaction of LH with uranyl nitrate in water/acetonitrile at 180 °C yields the complex [(UO2)3(L)(HL)(O)(OH)3] ·2.5H2O ·CH3CN ( 2), which is different from the previously reported complex [UO2(L)(OH)] ( 1). Complex 2 crystallizes as a ribbon-like 1D coordination polymer with a skeleton bridged by oxido and hydroxido ligands, in which the uranyl cation is bound to the bridging bidentate carboxylato groups, and the pyridyl groups (one of them protonated) are directed sideways. In the presence of copper nitrate, the reaction affords the heterometallic complex [(UO2)2Cu(L)3(O)(H2O)](NO3) ( 3), in which the harder uranium atom is bound to two μ3-oxido anions and to chelating and bridging carboxylato groups to generate a tetranuclear secondary building unit, whereas the softer copper cations are bound to three pyridyl groups and only one carboxylato donor. The copper atoms are further involved in cation-cation interactions with uranyl oxido groups, and the Cu-O(oxido) bond lengths of 2.162(13) and 2.248(16) Å are among the shortest measured to date. 3 crystallizes as a 3D assembly, which displays narrow channels, and it illustrates the ability of copper cations, in combination with a ditopic ligand, to assemble discrete uranyl-containing units into a framework structure. The emission spectra of complexes 1 and 2 in the solid state display the usual vibronic progression of the uranyl ion in the range 450-650 nm, and the width of the bands indicates that they may be the superposition of slightly different series, due to the inequivalent uranyl centres in the lattices. [ABSTRACT FROM AUTHOR]

The preparation by simple direct synthesis of a series of coordination polymers based on copper with chloride or bromide and dipyrimidinedisulfide is reported. The structural characterisations of these compounds reveal a rich structural variety as a result of the number of coordination modes available to the organosulfur ligand, in combination with the bridging capabilities of the halides. Interestingly, some of the polymers displayed fully reversible solvent exchange/removal crystal-to-crystal 2D to 0D and 2D to 2D transformations. These materials show multifunctional electronic properties. Thus, some of them are semiconductors and present weak antiferromagnetic interactions, and the CuI/CuII coordination polymers present coexistence of paramagnetism with weak red emission. These compounds present some of the lowest NIR energy luminescence in d10 transition-metal complexes. [ABSTRACT FROM AUTHOR]

By using [(Cp″′Co)2tol] (Cp″′ = η5-C5H2 tBu3, tol = toluene), a new synthesis of the 1,3-diphosphete complexes [Cp″′Co(η4-P2C2 tBu2)] ( 1a) and [Cp″′Co(η4-P2C2 iPr2)] ( 1b) was found, and their reactions with the Lewis acids W(CO)4 and CuI halides were investigated. The reaction of 1b with W(CO)4(nbd) (nbd = norbornadiene) leads to the complex [(Cp″′Co)(μ,η4:1-{PC iPr}2)]2W(CO)4 ( 2) with the two diphosphete complexes 1b coordinated trans to a central W(CO)4 moiety. The reactions of 1a with CuI halides result in different products depending on the stoichiometry. In a 1:1 ratio, the dimeric compounds 3a- c [(Cp″′Co)(μ,η4:1-{PC tBu}2)Cu(μ-X)]2 ( 3a: X = Cl; 3b: X = Br, 3c: X = I) were isolated, whereas an excess of CuX gave the two-dimensional polymers [({Cp″′Co}{μ3,η4:1:1-(PC tBu)2})2(Cu{μ3-X})4] n ( 6a: X = Cl, 6b: X = Br, 6c: X = I). From the reaction of 1a and 1b with CuBr and CuI in a 1:2 or 2:3 ratio, the one-dimensional polymers [({Cp″′Co}{μ3,η4:1:1-(PCR)2})({Cp″′Co}{μ,η4:1-(PCR)2})(Cu{μ3-X})4] n ( 4a: X = Br, R = iPr, 4b: X = I, R = iPr, 4c: X = I, R = tBu) are formed. From the reaction of 1a with CuI, a second product, [({Cp″′Co}{μ3,η4:1:1-(PC tBu)2})(Cu{μ3-I})4(MeCN)2] n ( 5), was isolated by using CH3CN for crystallization. The products were comprehensively characterized by spectroscopic methods, X-ray crystallography, and 31P magic angle spinning (MAS) NMR spectroscopy. [ABSTRACT FROM AUTHOR]

A new organic building block, TEPB, has been synthesized that comprises three 2-ethylthio-substituted pyrimidine groups coupled to one central phenyl ring at the 1-, 3- and 5-positions. TEPB exhibits a quasi-planar conformation due to its intramolecular C-H ···N hydrogen bonds. The assembly of TEPB with CuI and CuCl2 produced two flat coordination chains 1 and 2, both exhibiting similar assembly hierarchies from chain through 2D layer to 3D architecture. It was found that extensive S ···S and C-H ···S contacts exist in the 2D layers of 1 and 2, respectively. Between the 2D layers of 2, there are O-H ···Cl hydrogen-bonding interactions between water molecules and coordinated Cl atoms that provide a proton-transfer network. Complex 2 exhibits a smaller optical band gap (1.11 eV) than 1 (1.93 eV), which has been attributed to d-electron transition in the copper(II) ion. The d.c. conductivities of 1 and 2 at room temperature were measured to be 2.84 × 10-12 and 2.42 × 10-10 S cm-1, respectively. The a.c. conductivity of 2 obtained at room temperature by the complex impedance technique is about 5.90 × 10-9 S cm-1, which can be attributed largely to proton conduction. Moreover, the a.c. conductivity of 2 decreases almost linearly with increasing temperature, presumably as a result of its temperature-sensitive O-H ···Cl hydrogen-bonding network that allows for proton conduction. [ABSTRACT FROM AUTHOR]

5-Cyanotetrazole readily forms from (CN)2 and HN3. The coordination abilities of the 5-cyanotetrazolate anion N4CCN- (ctz) towards CuII ions were examined and a series of complexes and coordination polymers were synthesized and characterized by single-crystal structure analyses: PPh4[Cu(ctz)3] ( 1), [Cu(ctz)2(bipy)] ( 2, bipy = 2,2′-bipyridine), [CuCl(py)4](ctz) ·2py ( 3, py = pyridine), [Cu2(ctz)6Cu(CH3CN)2(H2O)2] ·2CH3CN ( 4a), [Cu2(ctz)6Cu(H2O)3{(CH3)2CO}] ·3(CH3)2CO ( 4b), [Cu(ctz)2(py)4] ( 5), [Cu2(ctz)4(bipy)2] ( 6) and [Cu2(ctz)2(tpm)2(NO3)]NO3 [ 7, tpm = tris(pyrazol-1-yl)methane]. As ctz is a multidentate linker, additional neutral coligands such as monodentate py, bidentate bipy and tridentate tpm ligands were used to avoid the formation of noncrystalline polymers. The structures of 1- 7 reflect the versatile coordination abilities of ctz in the various types of coordination environments of the CuII ions and dimensionalities of the linkages. The structures represent 1D chain motifs ( 1, 2 and 3), 2D layered structures ( 4a and 4b), mononuclear ( 5) and dinuclear complexes ( 6 and 7). Magnetic coupling phenomena were detected by susceptibility measurements of 1, 4a, 6 and 7, which were fitted to the magnetic models according to antiferromagnetic spin-pairing of two S = 1/2 systems (Bleaney-Bowers) for 6 ( J = -0.53 cm-1) and 7 ( J = -2.91 cm-1), to the ferromagnetic high-temperature series expansion based on the Baker 1D ( S = 1/2) chain model for 1 ( J = +14.4 cm-1) and to the Néel model of ferrimagnetism for 4a. The diverse magnetic interactions between the Cu2+ sites are communicated by the bridging ctz anions. [ABSTRACT FROM AUTHOR]

Four azide-copper coordination polymers, [Cu2L1(N3)4] n, [Cu2L2(N3)4] n, [Cu2L3 R(N3)4] n, and [Cu2L3 S(N3)4] n, were synthesized by using pybox [pyridine-2,6-bis(oxazolines)] as coligands {L 1: 2,6-bis(4,5-dihydrooxazol-2-yl)pyridine; L 2: 2,6-bis(5,6-dihydro-4 H-1,3-oxazin-2-yl)pyridine; L 3 R or 3 S: 2,6-bis[( R or S)-4-benzyl-4,5-dihydrooxazol-2-yl]pyridine}. Compounds 1 and 2 possess similar 1D infinite azide-copper hexagonal tapes with three types of N3 bridges (two single end-on N3 bridges and one double end-on N3 bridge). Compounds 3 R and 3 S possess an azide-copper 2D honeycomb layer with two types of N3 bridges (a single end-to-end N3 bridge and a double end-on N3 bridge). The chirality of these enantiopure layered structures is controlled by the addition of the chiral pybox ligand in the synthesis, which is very rare for the reported azide-copper coordination polymers. The double end-on N3 bridge transfers mainly ferromagnetic exchange coupling interactions in these four compounds. Owing to the steric hindrance of the pybox ligands, the interchain and interlayer separations are broadened, which weakens the magnetic interactions between them. Thus, no long-range ferromagnetic ordering was observed above 1.8 K. A magnetostructural correlation was also discussed in detail. [ABSTRACT FROM AUTHOR]

Five tetrazolate-based coordination polymers with cationic copper(I) halide motifs, namely, Cu4(tta)2Cl2 ( 1, tta = tetrazolate), Cu4(tta)2Br2 ( 2), Cu2(tta)I ( 3), Cu3(mtta)2Cl ( 4, mtta = 5-methyltetrazolate), and Cu2(tta)Br ( 5) were prepared by hydro(solvo)thermal reactions of CuX2 or CuX with tetrazolato ligands in the presence of HX. Compounds 1, 2, and 3 show eight-connected square-planar layered structures constructed with butterfly-like [Cu4X2]2+ (X = Cl, Br, I) clusters and μ4-tta groups. Isomorphs 1 and 2 crystallize in the orthorhombic space group Pbca, but 3 crystallizes in the orthorhombic space group Pbam, because each μ4-tta group is coordinated to three butterfly-like clusters rather than four in 1 and 2. To the best of our knowledge, 1, 2, and 3 represent the only 2D coordination polymers with eight-connected square planar topology to date. Compound 4 is a [Cu3Cl]2+ cluster based on the undocumented ten-connected ZrIn2 topological framework. Compound 5 has a 3D pillar layered framework constructed with [Cu2Br] nn+ cationic layers. Compounds 1, 2, 4, and 5 exhibit strong green-blue emission in the solid state at room temperature, whereas cuprous iodide complex 3 shows strong red luminescence. [ABSTRACT FROM AUTHOR]

This study examines the use of tetrahedral [E(O-C6X4-CN)4]- anions (E = B, Al; X = H, F), which can be synthesized from the reaction of tetrahedral NaBH4/LiAlH4 and HO-C6X4-CN, as anionic linkers for the generation of 2D and 3D crystalline coordination polymer networks. Such polymer networks were obtained by the connection of tetrahedral p-cyanophenoxy aluminate or borate linkers with monocationic metal centers such as Li+, Na+, Ag+, and Cu+. These studies are specifically focused on the synthesis, structure, and stability of such polymers. Additionally, the perfluorinated O-C6F4-CN linker was used to study electronic influences. Salts bearing the perfluorinated [E(O-C6F4-CN)4]- anion decompose into E(O-C6F4-CN)3 and [O-C6F4-CN]-, which is also observed when a Lewis acid such as B(C6F5)3 is added. Moreover, addition of B(C6F5)3 leads to the formation of molecular-ion pairs because the cyano groups are now either completely or partly blocked. The structures of M[Al(O-C6H4-CN)4] (M = Li, Ag, Cu), Na[B(O-C6H4-CN)4], and Li[Al(O-C6F4-CN)4] as well as of the decomposition products Na(O-C6F4-CN), (THF)Al[O-C6H4-CN ·B(C6F5)3]3 (THF = tetrahydrofuran), Na[(F5C6)3B ·O-C6H4-CN ·B(C6F5)3], and Li[NC-C6F4-O-Al{O-C6F4-CN ·B(C6F5)3}3] are discussed. [ABSTRACT FROM AUTHOR]

The use of α-benzoin oxime (bzoxH2) in copper(II) benzoate chemistry, in the absence or presence of ancillary azido ligands, is reported. The reaction of Cu(O2CPh)2 ·2H2O with one equivalent of bzoxH2 in N, N-dimethylformamide (DMF) affords the decanuclear complex [Cu10(bzox)10(DMF)4] ( 1) in good yield. Dissolution of 1 in CH2Cl2 leads to the subsequent isolation of the solvent-free complex [Cu10(bzox)10] ( 2) in moderate yields. Complexes 1 and 2 are isostructural and possess a loop or single-strand molecular wheel topology. The bzox2- dianions behave as η1:η1:η2:μ3 ligands, which give rise to an overall [Cu10(μ-ONR)10(μ-OR′)10] core. Both 1 and 2 stack to form nanotubular columns with beautiful supramolecular architectures. The reaction of Cu(O2CPh)2 ·2H2O with bzoxH2 and NaN3 in a 1:1:1 molar ratio in MeOH gives the bzoxH2-free complex [Cu(N3)(O2CPh)(MeOH)] n ( 3), which is a 1D chain. The CuII atoms in 3 are linked by a single, end-on N3- group, a syn, syn-η1:η1:μ PhCO2- ion, and an oxygen atom from the bridging MeOH ligand. The 1D chains are hydrogen bonded into 2D sheets through Nazide ···H(OMeOH) interactions. Variable-temperature, solid-state direct-current magnetic studies were carried out on 1- 3. The data for 1 and 2 indicate very strong antiferromagnetic exchange interactions and a S = 0 ground state, which is expected for even-membered loop arrays of CuII atoms. In contrast, 3 exhibits ferromagnetic exchange interactions; the data were fitted to the appropriate equation derived from the Hamiltonian H = - JΣ( Si · Si+1), which includes a zJ′ interchain interaction term. The best-fit parameters were J = +49.6(4) cm-1, g = 2.067(3), and zJ′ = 2.3(1) K. The combined results demonstrate the ligating flexibility of both the bzoxH2 and azido groups and their usefulness in the synthesis of polynuclear CuII clusters and coordination polymers. [ABSTRACT FROM AUTHOR]