Alternating Ferro/Antiferromagnetic Copper(II) Chain Containing an Unprecedented Triple Formato/Hydroxido/Sulfato Bridge.

The first example of a triple formato/hydroxido/sulfato (FHS) bridge for any metal is reported in compound [Cu2(bpym)(OH)(HCO2)(SO4)(H2O)2]·3H2O (1). Its structure shows the presence of alternating triple FHS bridges and 2,2'-bipyrimidine (bpym) ones. Although in the initial synthesis the sulfate anions were introduced accidentally, here we report the rational synthesis and the magnetic properties of this compound. The magnetic properties show that 1 is an alternating ferro/antiferromagnetic (F/AF) chain compound with predominant antiferromagnetic interactions and were fit to an alternating F/AF S = (1)/2 chain with g = 2.103, JAF = -139 cm(-1), and JF = 116 cm(-1) (α = JF/|JAF| = 0.83). Th…

Coordinating behaviour of a new pyridylhydrazone; tris-complexes of manganese(II), cobalt(II), nickel(II), copper(II) and zinc(II) with 2-pyridylcarbaldehyde-N,N-dimethylhydrazone

The preparation and characterization oftris-complexes of MnII, CoII, NiII, CuII and ZnII with a new pyridylhydrazone, 2-pyridylcarbaldehyde-N,N-dimethylhydrazone (pch), are described. In all the complexes pch behaves as a bidentate ligand binding through the pyridine and azomethyne nitrogen atoms. The complexes appear to be monomeric, high spin six-coordinate, and a distorted octahedral stereochemistry around the metal is suggested. The e.p.r. results for both CuII compounds indicate a mainly dx2−y2 ground state with a static Jahn-Teller distortion, whilst for the MnII complex the e.p.r. data indicates a very low symmetry for the MnN6 polyhedron.

Cooperative H-bonds, π⋯π and anion⋯π interactions as driving forces in the construction of novel Cu(II) bis(imidazol-2-yl) supramolecular 3D frameworks

Abstract Two new Cu(II) complexes with bis(2-imidazolyl) based ligands, with the formula [Cu(BIM)2(SCN)2]·2H2O (BIM = bis(2-imidazol-2-yl)methane) and [Cu(HBIMAM)2(OH2)2](BF4)4·2H2O (BIMAM = bis(2-imidazol-2-yl)methylaminomethane) have been synthesized and characterized. Both compounds contain mononuclear entities as molecular building blocks (MBBs); neutral [Cu(BIM)2(SCN)2] in compound 1 and cationic [Cu(HBIMAM)2(OH2)2]4+ in compound 2. The coordination around the metal atoms shows a tetragonally-elongated octahedral geometry (CuN4S2 and CuN4O2 chromophores). The Q-band EPR spectra of both compounds are indicative of an essentially d x 2 - y 2 ground state for copper(II) ions. The analysis…

X-ray crystal structure and electronic properties of chlorobis(mepirizole)copper(II) tetrafluoroborate (mepirizole = 4-methoxy-2-(5-methoxy-3-methyl-1H-pyrazol-1-yl)-6-methylpyrimidine)

Abstract The crystal structure of [Cu(mep)2Cl](BF4)[mep = 4-methoxy-2-(5-methoxy-3-methyl-1H-pyrazol-1-yl)-6-methylpyrimidine] has been determined by X-ray diffraction. The crystal structure is built up of [Cu(mep)2Cl]+ cations and BF4− anions. The structure of the cation involves a five-coordinated CuN4Cl chromophore, with a stereochemistry near to a compressed trigonal bypyramid (TBP) but with a significant degree of distortion towards the square pyramidal (SP) topology. The EPR spectrum is indicative of a mixed dz2/dx2 − y2 ground state for the copper(II) ions, in agreement with the structural data.

Synthesis of new terpyridine-like ligands based on triazolopyridines and benzotriazoles

Herein, terpyridine triazole-based analogs bearing benzotriazoles or/and triazolopyridines are prepared via copper catalysis, where the arrangement of the nitrogen atoms is proven to be crucial to the spectroscopic properties of these ligands.

Synthesis and spectral studies ofN-2-pyridinylcarbonyl-2-pyridinecarxoximidate copper(II) complexes

Dimeric and polymeric copper(II) complexes containing BPCA (N-2-pyridinylcarbonyl-2-pyridinecarboximidate), having general formulae Cu(BPCA)X·nH2O (X=Cl, Br, NCS, NCO, N3, or CN) and Cu2(BPCA)2-X·nH2O [X=oxalate anion (OX), chloranilate anion (CA) or the dianion of 2,5-dihydroxy-1,4-benzoquinone (DHBQ)] have been synthesized by the copper(II)-assisted hydrolysis of 2, 4, 6-tris(2-pyridyl)-1, 3, 5-triazine. Spectroscopic results indicate five-coordinate, approximately square-pyramidal, geometry around the copper(II) ion. Half-field absorption in the ΔMs=±2 region of the X-band e.p.r. powder spectra has been observed for the dimeric species.

Order and disorder in mixed metal linear chains: The homo and heterobimetallic EDTA (M(H2O)4OIOII)[M?(EDTA)] � 6H2O complexes (M = Mg, Mn, Co, Zn and Ni; M? = Co, Ni, Cu and Zn)

Polymetallic solid solutions of the ethylenediaminetetracetic acid (EDTA) and six divalent metal ions exist in the range: MgαMnβCoγZnδNieCuτ(EDTA) · 6H2O where α + β + γ + δ + e + τ=2, 0⩽τ⩽1, 0⩽γ,e,δ⩽2, 0⩽α, β⩽1. This type of structure is characterized by the presence of two different octahedral carboxylate-bridged coordination sites forming infinite zig-zag chains. Visible and i.r. spectra and t.g.a. analysis show that there is occupational preference for the two coordination sites in the crystalline structure. Due to this preference, and also to the structural features, the heterobimetallic MM′(EDTA) · 6H2O compounds constitute a structurally new class of materials which can be described …

Structure, spectroscopic and magnetic properties of a novel 1-D coordination copper(II) polymer containing BIMAM ligand [BIMAM=bis(imidazol-2-yl)methylaminomethane] and μ-1,3 squarato bridges

Abstract This paper reports the synthesis and complete characterization (structural, spectroscopic and magnetic) of [Cu(HBIMAM)Cl(C4O4)]n · (H2O)n [BIMAM = bis(imidazol-2-yl)methylaminomethane]. This compound is made of infinite chains – running along c axis – built from [CuCl(HBIMAM)]+ units bridged together by μ-O1,O3-bis(monodentate) squarate anions. Non-covalent interactions (H-bonds and π–π) drive the build-up of an infinite three-dimensional array. The coordination polyhedron about the copper(II) ion is distorted square pyramidal. The EPR spectrum is indicative of a d z 2 - y 2 ground state for the Cu(II) ions with significant contribution of d z 2 . Magnetic susceptibility measuremen…

A rare example of nickel(ii) chains based on a heteroscorpionate-like ligand with quadruple imidazolyl interactions

The first nickel(ii) complex with the heteroscorpionate-like bridging ligand DIMMAL (2-di1H-2-imidazolylmethylmalonate), [Ni(DIMMAL)(H2O)3]n·3nH2O (1), is a one-dimensional coordination polymer whose structure shows regular Ni(ii) chains with H-bonding inter-chain interactions and a rare example of a Quadruple Imidazolyl Embrace (QIE). The Ni(ii) chain shows a weak antiferromagnetic interaction that can be modelled with a regular S = 1 chain model including a zero field splitting with g = 2.270, J = -1.5 cm(-1) and D = -2.26 cm(-1).

Correction: A C(π-hole)⋯Cl–Zn tetrel interaction driving a metal–organic supramolecular assembly

Correction for ‘A C(π-hole)⋯Cl–Zn tetrel interaction driving a metal–organic supramolecular assembly’ by Carmen Ramírez de Arellano et al., CrystEngComm, 2020, 22, 6979–6982, DOI: 10.1039/D0CE01272F.

Study of the thermal behaviour of ordered bimetallic EDTA complexes

Abstract The study of the thermal behaviour of a family of isostructural ordered bimetallic MM'(EDTA)·6H 2 O complexes has been performed using TG and DTA. Formal kinetic analysis of the dehydration step has been approached using non-isothermal procedures. The resulting correlation among the calculated E a values and the cationic sizes implies a common dehydration mechanism. Copper-containing complexes show distinctive behaviour during the ligand pyrolysis processes. A mechanistic interpretation involving formation of Cu(I) and Cu(0) intermediates is furnished. The evolution of the inorganic residues in systems containing both Co and Ni is especially considered given the interest in the (Co…

A novel dinuclear manganese(II) compound incorporating two bis(imidazolyl) based ligands with single μ2-η1:η1-carboxylato bridges. Molecular and crystal structure and magnetic properties of [Mn2Cl(BIP)(HBIMAM)(H2O)5]Cl3·4H2O (BIP=3,3-di(2-1H-2-imidazolyl)propanoate; BIMAM=N-methyldi(1H-2-imidazolyl)methanamine)

Abstract This paper reports the synthesis, X-ray structure and magnetic characterization of [Mn 2 Cl(BIP) (HBIMAM)(H 2 O) 5 ]Cl 3 ·4H 2 O a novel dinuclear manganese(II) incorporating two related bis(imidazolyl)-based ligands, BIP (3,3-di(2-1 H -2-imidazolyl)propanoate) and BIMAM ( N -methyldi(1 H -2-imidazolyl)methanamine). The metal atoms in the dinuclear entity are bridged by a μ 2 -η 1 :η 1 carboxylate group (from the propionate arm of the BIP ligand) acting in an anti – anti coordination bridging mode, with an intramolecular Mn⋯Mn distance of 6.47 A. The coordination around the Mn(II) ions shows a distorted octahedral geometry for both MnClN 2 O 3 and MnN 2 O 4 chromophores. Between th…

Exchange interactions through hydrogen-bond bridges. Crystal structure, spectroscopic characterisation and magnetic properties of the complex [{Cu(en)}2(μ-egta)]·4H2O (H4egta = 3,12-bis(carboxymethyl)-6,9-dioxa-3,12-diazatetradecanedionic acid)

Abstract The structure and spectroscopic and magnetic properties of [{Cu(en)}2(μ-egta)]·4H2O (H4egta = 3,12-bis(carboxymethyl)-6–9-dio 3,12-diazatetradecanedioic acid) are described. The compound is built of centrosymmetric neutral dimeric {[Cu(en)}2(μ-egta)] entities linked through hydrogen bonds involving water molecules. -NH2 groups and -CO2 groups, affording a three-dimensional framework. The egta anion displays an opened-up structure acting as a bridging ligand between two copper atoms. The coordination geometry about the metal atoms can be viewed as 4 + 1 + 1 (CuN3OO′O″ chromophores). The EPR spectra are indicative of an essentially dv−v ground state for the copper(II) ions. Magnetic …

Mono and dinuclear copper(II) complexes of 2,4,6-tris(2-pyridyl)-1, 3,5-triazine and halide or pseudohalide ions: Synthesis and spectral studies

By inhibiting the copper(II) assisted TPT (TPT = 2,4,6-tris(2-pyridyl)-1,3,5-triazine) hydrolysis, monomeric and dimeric copper(II) complexes having as general formulae Cu(TPT)X, · nH2O (X = Cl, Br, NCS, NCO or N3) and [Cu(TPT)X]2(PF6)2 · nH2O (X = Cl, Br, NCS or N3) have been synthesized and characterized by i.r., electronic and e.p.r. spectra, x-ray powder diffraction and analytical data. Spectroscopic results indicate five-coordinate geometry around the copper(II) ion, intermediate between trigonal-bipyramid and square-pyramid structures. The half-field absorption in the ΔMS = 2 region of powdered X-band e.p.r. spectra has been observed for the dimeric species.

Crystal and molecular structure of tris(mepirizole) copper(II) hexafluorophosphate [mepirizole = 4-methoxy-2-5-methoxy-3-methyl-1h-pyrazol-1-yl)-6-methylpyrimidine

Abstract The X-ray crystal structure of Cu(mep)3(PF6)2 [mep = mepirizole or 4-methoxy-2-(5-methoxy-3-methyl-1H-pyrazol-1-yl)-6 methylpyrimidine], obtained from stoichiometric quantities of mep, Cu(NO3)2 and KPF6 in water/ethanol solution was determined. The trisbidentate Cu(mep)32+ cation is observed for the first time. One of the three mep molecules is disordered over two sets of positions related by crystallographic symmetry. The mep molecules exhibit two different conformations A and B: conformation B, which is observed for the first time, derives from the usual conformation A by rotating the pyrimidine ring by 180° around the central CN bond and rotating by 180° the methoxy group bonde…

Synthesis, Crystal Structure, and Magnetic Properties of Oxalato-Copper(II) Complexes with 3,3-Bis(2-imidazolyl)propionic Acid, an Imidazole-Carboxylate Polyfunctional Ligand: From Mononuclear Entities to Ladder-Like Chains.

The synthesis of five new Cu(II) compounds of formula [Cu(HBIP)(C(2)O(4))].H(2)O (1), [Cu(HBIP)(C(2)O(4))(OH(2))].2H(2)O (2), [{Cu(HBIP)Cl}(2)(mgr;-C(2)O(4))].2H(2)O (3), [{Cu(BIP)}(2)(mgr;-C(2)O(4))].2H(2)O (4) and [{Cu(BIP)}(2)(mgr;-C(2)O(4))].6H(2)O (5), together with their spectral and magnetic characterization, is reported. Crystal structures of compounds 2, 3 and 5 have been solved. All these compounds crystallize in the triclinic system, space group Ponemacr;, with a = 7.3322(3) Å, b = 10.014(1) Å, c = 11.541(1) Å, alpha = 113.22(1) degrees, beta = 91.37(1) degrees, gamma = 94.51(1) degrees, Z = 2 for compound 2; a = 7.444(2) Å, b = 8.518(2) Å, c = 11.231(2) Å, alpha = 97.45(2) degre…

Crystal structure, magnetic and spectroscopic properties of the bis(dimethyl sulfoxide) adduct of tetra-μ-formato-dicopper(II), a new tetracarboxylato-bridged copper(II) dimer

The crystal and molecular structure of a new tetracarboxylato-bridged copper(II) dimer, the bis(dimethyl sulfoxide)tetrakis(μ-formato)dicopper(II) has been determined by X-ray diffraction methods. It crystatlizes in the tetragonal space group I41/a, with Z=8 in a cell of dimensions a=17.688(2), c=10.408(1) Å. The structure is built up of centrosymmetric neutral dimers [Cu2(HCOO)4(dmso)2], where four bidentate carboxylate anions form syn-syn bridges between the metal atoms which are in a 4 + 1 environment. Magnetic susceptibility data show that the copper atoms are strongly antiferromagnetically coupled with J=-434 cm-1. The obtained triplet-singlet energy gap is compared with those reported…

Crystal structure, spectroscopic characterisation and magnetic properties of [Cu(BIP)(N3)]·H2O (BIP=3,3-bis(2-imidazolyl)propionate), a copper(II) polymeric compound with asymmetrical μ-1,3-azido bridges

Abstract The structure and the spectroscopic and magnetic properties of [3,3-bis(2-imidazolyl)propionato]azidocopper(II) monohydrate are described. The compound is built of [Cu(BIP)N3] entities which are connected through carboxylate groups from the BIP molecules —which act as a tridentate ligand—and asymmetrical μ-1,3-azido bridges, leading to a polymeric sheet-like structure. The copper atom is involved in a CuN3ON′ chromophore and lies in a distorted square-pyramidal environment. Both electronic and EPR spectra are indicative of an essentially dx2−y2 ground state for the copper(II) ions. Magnetic susceptibility measurements in the range 1.8–200 K show very weak antiferromagnetic exchange…

Synthesis, crystal structure, spectroscopic characterisation and magnetic properties of [Cu2(BIBM)2(C2O4)2]·4H2O (BIBM=bis(2-imidazolyl)bis(methoxycarbonyl)methylmethane)

Abstract The structure and spectroscopic and magnetic properties of bis(μ-1,2,3-oxalato)bis[bis(2-imidazolyl)bis(methoxycarbonyl)methylmethane]dicopper(II) tetrahydrate are described. The compound is built of centrosymmetric neutral dimeric [Cu2(BIBM)2(C2O4)2] entities linked through hydrogen bonds involving water molecules and oxalate groups. In the dimeric unit the two centrosymmetrically related copper — which are involved in CuN2O2O2′ chromophores lying in an elongated octahedral environment — are bridged through the oxalate group which acts in a bidentate–monodentate (μ-1,2,3) fashion. Both electronic and EPR spectra are indicative of an essentially dx2−y2 ground state for the copper(I…

Synthesis and Spectroscopic Characterisation ofbis-Complexes of Cobalt(II), Nickel(II) and Copper(II) with N,N,N′N′-Tetraethylpyridinecarboxamide

Abstract Bis-complexes of Co(II), Ni(II) and Cu(II) with tedpa (N,N,N′N′-tetraethyl-pyridinedicarboxamide) having the general formula [M(tedpa)2]X2 (X = ClO4, PF6) have been synthesized and characterised by i.r., electronic and e.p.r. spectra. The spectroscopic results suggest that the tedpa acts in these compounds as tridentate ligand through two oxygen atoms and a nitrogen (from the pyridine ring) atom. A distorted octahedral environment (MN2O4 chromophores) for the metal atoms is inferred from the spectroscopic data.

Structural, magnetic, and spectroscopic comparative studies on four new derivatives of DIMMAL (2-di1H-2-imidazolylmethylmalonate): a novel generator of multidimensional networks.

This paper reports the synthesis, structure solution, and magnetic characterization of four new DIMMAL-containing compounds (H 2 DIMMAL = 2-di1H-2-imidazolylmethylmalonic acid), H 2 DIMMAL.H 2 O (1), Na 2 (DIMMAL).5H 2 O (2), [Cu(HDIMMAL) 2 ] (3), and [Cu 2 (DIMMAL) 2 (H 2 O) 2 ].2H 2 O (4). Compound 1, containing two carboxylates and two protonated imidazole rings, adopts the dizwitterion configuration. These monohydrate MBBs pack together into a 3D array driven, as in the other three cases herein reported, by a combination of multiple-path H-bonds and aromatic-aromatic interactions. Compound 2 consists of centrosymmetric Na + tetramers in which four NaO 6 distorted octahedra are interconn…

Novel Cu(II)-Based Frameworks Built from BIMAM and Oxalate: Syntheses, Structures, and Magnetic Characterizations (BIMAM = Bis(imidazol-yl) methylaminomethane)

Complexes with the formula [Cu(HBIMAM)(C2O4)]2[Cu(C2O4)2(OH2)2] (1) and [{Cu(HBIMAM)(OH2)(OClO3)}2(μ-C2O4)] (ClO4)2 (2) have been synthesized from copper(II) perchlorate, bis(imidazol-yl) methylami...

Kineticversus thermodynamic synthesis pathways of solid bimetallic coordination compounds ? Synthesis and crystal structure of some bimetallic compounds of glycineN,N?-1,2-cyclohexanedylbis[N-(carboxymethyl)]

Synthesis, Crystal Structure, Magnetic Properties, and Theoretical Studies of [{Cu(mepirizole)Br}2(μ-OH)(μ-pz)] (Mepirizole = 4-Methoxy-2-(5-methoxy-3-methyl-1H-pyrazol-1-yl)-6-methylpyrimidine; pz = Pyrazolate), a Novel μ-Pyrazolato−μ-Hydroxo-Dibridged Copper(II) Complex

A novel mu-pyrazolato-mu-hydroxo-dibridged copper(II) complex has been synthesized and structurally characterized: [(Cu(mepirizole)Br)2(mu-OH)(mu-pz)] (mepirizole=4-methoxy-2-(5-methoxy-3-methyl-1H-pyrazol-1-yl)-6-methylpyrimidine; pz=pyrazolate). The title compound crystallizes in the monoclinic system, space group P2(1)/c, with a=15.618(2) A, b=15.369(3) A, c=16.071(3) A, and beta=112.250(1) degrees. The structure is built up of dinuclear [(Cu(mepirizole)Br)2(mu-OH)(mu-pz)] units with five-coordinated copper(II) ions (CuBrN3O chromophores) linked by mu2-OH and mu2-pyrazolato bridges that are well separated from each others. The intramolecular copper-copper distance is 3.378(3) A. Magnetic…

Synthesis and characterization of mono- and binuclear copper(II) complexes with 2,2′:6′,2″-terpyridine (terpy) and carboxylates: X-ray crystal structure of [Cu(terpy)(OOCH)(OH2)](ClO4) complex

Abstract Perchlorate and hexafluorophosphate salts of monomeric [Cu(terpy)(OOCH)(OH2)]+ and dimeric [Cu(terpy)(OOCR)]22+ cations (terpy = 2,2′:6′,2″-terpyridine, R = CH3 or C2H5) have been synthesized and characterized by IR, electronic and ESR spectra, and analytical data. Spectroscopic results indicate a five-coordinate, close-to-square pyramidal geometry around the copper(II) ion. The half-field absorption in the ΔMs = 2 region of powdered X-band ESR spectra has been observed for the dimeric species. The crystal structure of [Cu(terpy)(OOCH)(OH2)](ClO4) has been determined by X-ray diffraction methods. The compound crystallizes in the space group P21/c with unit-cell dimensions: a = 7.34…

Design of ordered bimetallic complexes, Part 2:Trans-1,2-cyclohexanediaminetetraacetate bimetallates

Knowledge of the kinetic and thermodynamic behaviour of aqueous solutions containing two divalent cations andtrans-1,2-cyclohexanediaminetetraacetate has been used to design synthetic pathways to ordered bimetallic complexes

Two Polymeric Compounds Built from Mononuclear and Tetrameric Squarate−Copper(II) Complexes by Deprotonation of 3,3-Bis(2-imidazolyl)propionic Acid (HBIP). Synthesis, Crystal Structure, and Magnetic Characterization of [Cu(HBIP)(BIP)](C4O4)1/2·2H2O and [{Cu(BIP)(OH2)}4(μ-C4O4)](ClO4)2·4H2O

Two polynuclear copper(II)−squarate compounds of formulas [Cu(HBIP)(BIP)](C4O4)1/2·2H2O (1) and [{Cu(BIP)(OH2)}4(μ-C4O4)](ClO4)2·4H2O (2) (HBIP = 3,3-bis(2-imidazolyl)propionic acid) have been synthesized and characterized by single-crystal X-ray diffraction. Both compounds crystallize in the triclinic system, space group P1, with a =7.947(1) A, b =12.327(4) A, c = 13.150(3) A, α = 113.91(2)°, β = 99.85(2)°, γ = 90.02(2)° for compound 1 and a = 8.010(1) A, b = 13.073(1) A, c = 14.561(1) A, α = 72.13(1)°, β = 80.14(1)°, γ = 84.02(1)° for compound 2. The structure of compound 1 can be viewed as made up of [Cu(HBIP)(BIP)] units linked together by the BIP carboxylate groups to form a one-dimens…

Mononuclear and binuclear copper(II) complexes with bis(2-imidazolyl)(bis(methoxycarbonyl)methylmethane) (BIBM), a tripodal bis(imidazole) based ligand. Synthesis, crystal structure and magnetic Characterization of [Cu(BIBM)2](ClO4)2 and [{Cu(BIBM)(H2O)}2(μ1,2,3,4-C2O4)](C4O4)·6H2O

Two new Cu(II) complexes with bis(2-imidazolyl) (bis(methoxycarbonyl)methylmethane) (BIBM), a tridentate bis(imidazole) based ligand with the formula [Cu(BIBM) 2 ](ClO 4 ) 2 ( 1 ) and [{Cu(BIBM)(H 2 O)} 2 (μ 1,2,3,4 -C 2 O 4 )](C 4 O 4 )·6H 2 O ( 2 ) have been synthesized and characterized. Compound 1 shows mononuclear cationic [Cu(BIBM) 2 ] 2+ units and perchlorate ions. The coordination around the Cu(II) ion shows a tetragonally-elongated octahedral geometry. The BIBM ligand acts as a k 3 -N,N’,O tripodal ligand, through two imidazole N atoms and a weak Cu–O(carboxymethyl) axial interaction. In the crystal structure cations and anions connect through H-bonds generating linear chains. Line…

Pseudohalide derivatives of manganese(II) and copper(II) complexes with mepirizole, a biologically active pyrimidyl-pyrazole ligand

Abstract The synthesis and characterization of thiocyanate and azide derivatives of mepirizole(4-methoxy-2-(5-methoxy-3-methyl-pyrazol-1-yl)-6-methylpyrimidine, hereinafter L) with manganese(II) and copper(II) is reported. The compounds were characterized by IR, electronic and EPR spectra and analytical data. Spectroscopic results suggest the existence of dimeric neutral entities [L2Cu2(μ-X)2(X)2] (X = NCS or N3) with unsymmetrical end-to-end bridges and five-coordination geometry around the copper(II) ion. Magnetic susceptibility data show that in the azide derivative the copper atoms are antiferromagnetically coupled (J = −18 cm−1), but no magnetic exchange interaction could be detected i…

Crystal and molecular structure and electronic properties of [Cu(phen)2(HL)] · (phen)0.5 · 7H2O (H3L = 1,3,5-triazine-2,4,6(1H,3H,5H)-trione), a novel N-cyanurate(2-) derivative

Abstract The crystal and molecular structure of [Cu(phen)2(HL) · (phen)0.5 · 7H2O (H2L = 1,3,5-triazine-2,4,6(1H,3H,5H)-trione) has been determined by X-ray diffraction methods. The structure is built up of neutral [Cu(phen)2(HL)] entities (which are associated to form dinuclear units through hydrogen bonds involving the cyanurate ions), uncoordinated phenanthroline and crystallisation water molecules. The copper atom is involved in a CuN5 chromophore, with an stereochemistry near to a compressed trigonal bipyramid (TBP) but with a significant degree of distortion towards the square pyramidal (SP) topology. The EPR spectrum is indicative of a mixed d z 2 d x 2 −y 2 ground state for the copp…

A C(π-hole)⋯Cl-Zn tetrel interaction driving a metal-organic supramolecular assembly

A brominated pyrimidinyl triazolopyridine ligand (bptpy) forms a C(π-hole)⋯Cl-Zn tetrel interaction that plays a determining role in the formation of supramolecular layers through chain assembly in 18 membered metallacycle [(ZnCl2)2(μ-bptpy)2] crystals. Supramolecular chains are formed through C-H⋯X interactions. The observed interactions are supported by DFT calculations using model dimers. This journal is

Hydrogen bonding versus π-stacking in ferromagnetic interactions. Studies on a copper triazolopyridine complex

Magnetic susceptibility measurements show weak ferromagnetic exchange between the copper(II) ions of a novel triazolopyridine derivative [Cu(TPT)(H2O)2(BF4)](BF4)·2H2O (TPT = 3-{6-([1,2,3]triazolo[1,5-a]pyrid-3-yl)-2-pyridyl}-[1,2,3]triazolo[1,5-a]pyridine). Mononuclear [Cu(TPT)(H2O)2(BF4)]+ entities are connected through O–H⋯F, C–H⋯F and π⋯π interactions to give a 3D framework. Ferromagnetic properties are discussed on the basis of the interactions network.

Hexahalorhenate(iv) salts of protonated ciprofloxacin: antibiotic-based single-ion magnets

Two novel Re(IV) compounds of formula [H2cip][Hcip][ReCl6]Cl·H2O (1) and [Hcip]2[ReBr6] (2) [(H2cip)2+/(Hcip)+ = ciprofloxacindiium cation / ciprofloxacinium cation] have been synthesized and studied structurally and magnetically. 1 crystallizes in the monoclinic system with space group P21/c, whereas 2 crystallizes in the orthorhombic system with space group Pbca. 1 and 2 are hexahalorhenate(IV) salts obtained with the protonated ciprofloxacin antibiotic. In their crystal lattice, the [ReX6]2− [X = Cl(1) and Br(2)] anions are well separated from each other through the protonated ciprofloxacindiium (1) and ciprofloxacinium (1 and 2) cations, which are arranged without generating intermolecu…

New dinuclear copper complexes incorporating bis(imidazolyl) based ligands and bidentate–monodentate oxalate bridges. Crystal structure and magnetic properties of [Cu2(BIM)2(C2O4)2]·4H2O and [Cu2(BIK)2(C2O4)2] (BIM=bis(2-imidazolyl)methane), BIK=bis(2-imidazolyl)ketone). Exploring magneto-structural correlations

Abstract This paper reports the synthesis, X-ray crystal structure and magnetic characterization of two novel copper(II) dinuclear compounds including bis(imidazolyl) ligands and oxalate anions, [Cu2(BIM)2(C2O4)2]·4H2O (1) (BIM = bis(2-imidazolyl)methane) and [Cu2(BIK)2(C2O4)2] (2) (BIK = bis(2-imidazolyl)ketone). The oxalate anion acts as bidentate–monodentate in both cases, although it exhibits different coordination bridging modes: whereas in compound 1 a μ1,1,2-oxalato is observed, a μ1,2,3-oxalato is found in compound 2. In both cases, the 3D framework is held together by a combination of H-bonding and aromatic-aromatic interactions provided by the convenient structural features of BIM…

A novel coordination polymer with an unusual [3×2] oblique copper(II) grid: [Cu2(HBIMAM)2(C4O4)3(H2O)2]n·2nH2O [BIMAM=bis(imidazol-2-yl)methylaminomethane]. X-ray structure and magnetic characterization

Abstract This paper reports the synthesis, X-ray structure and magnetic characterization of [Cu2(HBIMAM)2(C4O4)3(H2O)2]n·2nH2O [BIMAM = bis(imidazol-2-yl)methylamino methane]. This compound is made of infinite chains – running along the [1 1 0] direction – with copper ions bridged by μ1,3-squarato ligands. Furthermore, these chains are further cross-linked through additional squarate anions (with the same μ1,3-bis(monodentate) bridging mode) to generate two-dimensional sheets parallel to the ab plane. There are inter-chains links every two copper atoms in a chain, forming an unusual (3 × 2) oblique copper(II) grid. Magnetic susceptibility measurements in the range 2–300 K show weak antiferr…

Crystal and molecular structure, and electronic properties of hexakis(imidazole)copper(II) formate

The crystal and molecular structure of [Cu(Im)6] (HCOO)2 (Im = imidazole) has been determined by X-ray diffraction methods. The compound is built of centrosymmetric Cu(Im) inf6 sup2− cations and non-coordinated HCO2 − anions, linked through H-bonds giving a layered structure in the ac plane. The coordination polyhedron around the Cu atoms can be described as a rhombically-distorted octahedron (CuN2N′2N′'2 chromophores). Both electronic and e.p.r. spectra are indicative of an essentially d x2− y2 ground state for the CuII ions. No exchange coupling has been detected down to 4.2 K by means of magnetic susceptibility measurements. This feature is discussed on the basis of the structural data.

Extended structures of copper(II) complexes with 2-di1H-2-imidazolylmethylmalonate (DIMMAL), a versatile bis(imidazole)–bis(carboxylate) ligand: Solution studies, crystal structures and spectroscopic characterization

Abstract Copper(II) complexes of 2-di1H-2-imidazolylmethylmalonate (DIMMAL) have been studied by potentiometric methods. The data revealed that the CuHL 2 - and CuL 2 2 - species are prevalent in the studied pH range. Moreover, this paper reports the synthesis, structure solution and spectroscopic characterization of two new DIMMAL containing complexes, (NH4)2[Cu(DIMMAL)2] · 4H2O (1) and [Cu(DIMMAL)(en)(H2O)] · 5H2O (2). The structure of compound 1 consists of centrosymmetric mononuclear anionic [Cu(DIMMAL)2]2− units, NH 4 + cations and lattice water molecules, in which DIMMAL2− acts as a tridentate ligand through two imidazole nitrogen atoms and one oxygen atom from a carboxylate group. Th…

Coordinating behaviour of 3-methyl[1,2,3]triazolo[1,5-a]pyridine (tzpy): crystal and molecular structure and electronic properties of [Cu(tzpy)2(ONO2)2(OH2)]

Abstract The crystal and molecular structure of [Cu(tzpy) 2 (ONO 2 ) 2 (OH 2 )] (tzpy=3-methyl[1,2,3]triazolo[1,5- a ]pyridine) has been determined by X-ray diffraction methods. The crystal structure is built up of discrete [Cu(tzpy) 2 (ONO 2 ) 2 (OH 2 )] entities linked through hydrogen bonds. The coordination geometry around the copper atom can be described as an elongated and strongly distorted octahedron displaying a 4+1+1* coordination mode (CuN 2 O 2 O′O″ chromophore), with one of the nitrato groups acting as bidentate and involved in a weak off-the- z -axis coordination. Spectroscopic properties are interpreted on the basis of the above stereochemistry.

CCDC 2026029: Experimental Crystal Structure Determination

Related Article: Carmen Ramírez de Arellano, Rosa Adam, Rafael Ballesteros-Garrido, Belen Abarca, Rafael Ballesteros, Ibon Alcorta, José Elguero, Emilio Escrivà|2020|CrystEngComm|22|6979|doi:10.1039/D0CE01272F

CCDC 1439890: Experimental Crystal Structure Determination

Related Article: Emilio Escrivà, José-Vicente Folgado, Guillermo Mínguez Espallargas, Lucia Soto, Amparo Sancho, Lourdes Perelló, Rosa Ortíz|2016|Polyhedron|112|137|doi:10.1016/j.poly.2016.03.041

CCDC 1469282: Experimental Crystal Structure Determination

Related Article: Carlos J. Gómez-García, Emilio Escrivà, Samia Benmansour, Juan J. Borràs-Almenar, José-Vicente Folgado, and Carmen Ramírez de Arellano|2016|Inorg.Chem.|55|2664|doi:10.1021/acs.inorgchem.6b00105

CCDC 1469281: Experimental Crystal Structure Determination

Related Article: Carlos J. Gómez-García, Emilio Escrivà, Samia Benmansour, Juan J. Borràs-Almenar, José-Vicente Folgado, and Carmen Ramírez de Arellano|2016|Inorg.Chem.|55|2664|doi:10.1021/acs.inorgchem.6b00105

CCDC 1439889: Experimental Crystal Structure Determination

Related Article: Emilio Escrivà, José-Vicente Folgado, Guillermo Mínguez Espallargas, Lucia Soto, Amparo Sancho, Lourdes Perelló, Rosa Ortíz|2016|Polyhedron|112|137|doi:10.1016/j.poly.2016.03.041

CCDC 1910411: Experimental Crystal Structure Determination

Related Article: Emilio Escrivà, José-Vicente Folgado, Amparo Sancho, Rosa Ortíz, Lourdes Perelló, Carmen Ramírez de Arellano|2019|Polyhedron|171|137|doi:10.1016/j.poly.2019.06.054

CCDC 2026030: Experimental Crystal Structure Determination

Related Article: Carmen Ramírez de Arellano, Rosa Adam, Rafael Ballesteros-Garrido, Belen Abarca, Rafael Ballesteros, Ibon Alcorta, José Elguero, Emilio Escrivà|2020|CrystEngComm|22|6979|doi:10.1039/D0CE01272F

CCDC 1910410: Experimental Crystal Structure Determination

Related Article: Emilio Escrivà, José-Vicente Folgado, Amparo Sancho, Rosa Ortíz, Lourdes Perelló, Carmen Ramírez de Arellano|2019|Polyhedron|171|137|doi:10.1016/j.poly.2019.06.054