Tris(3,5‐dimethylpyrazolyl)methane‐Based Heterobimetallic Complexes that Contain Zn and CdTransition‐Metal Bonds: Synthesis,Structures, and Quantum Chemical Calculations

Reactions of the tris(3,5‐dimethylpyrazolyl)methanide amido complexes [M′{C(3,5‐Me₂pz)₃}{N(SiMe₃)₂}] (M′=Mg ( 1 a ), Zn ( 1 b ), Cd ( 1 c ); 3,5‐Me₂pz=3,5‐dimethylpyrazolyl) with two equivalents of the acidic Group 6 cyclopentadienyl (Cp) tricarbonyl hydrides [MCp(CO)₃H] (M=Cr ( 2 a ), Mo ( 2 b )) gave different types of heterobimetallic complex. In each case, two reactions took place, namely the conversion of the tris(3,5‐dimethylpyrazolyl)methanide ligand (Tpmd*) into the ‐methane derivative (Tpm*) and the reaction of the acidic hydride M?H bond with the M′?N(SiMe₃)₂ moiety. The latter produces HN(SiMe₃)₂ as a byproduct. The Group 2 representatives [Mg(Tpm*){MCp(CO)₃}₂(thf)] ( 3 a / b ) form isocarbonyl bridges between the magnesium and chromium/molybdenum centres, whereas direct metal–metal bonds are formed in the case of the ions [Zn(Tpm*){MCp(CO)₃}]⁺ ( 4 a / b ; [MCp(CO)₃]^? as the counteranion) and [Cd(Tpm*){MCp(CO)₃}(thf)]⁺ ( 5 a / b ; [Cd{MCp(CO)₃}₃]^? as the counteranion). Complexes 4 a and 5 a / b are the first complexes that contain Zn?Cr, Cd?Cr, and Cd?Mo bonds (bond lengths 251.6, 269.8, and 278.9 pm, respectively). Quantum chemical calculations on 4 a / b* (and also on 5 a / b* ) provide evidence for an interaction between the metal atoms.     

A Copper‐Based Metal–Organic Framework Acts as a Bifunctional Catalyst for the Homocoupling of Arylboronic Acids and Epoxidation of Olefins

A copper(I)‐based metal–organic framework ({[Cu₂Br₂(pypz)]_n?nH₂O} (Cu—Br–MOF) [pypz=bis[3,5‐dimethyl‐4‐(4’‐pyridyl)pyrazol‐1‐yl] methane] has been synthesized by using an elongated and flexible bridging ligand. The structure analysis reveals that each pypz ligand acts as a tritopic ligand connected to two Cu₂Br₂ dimeric units, forming a one‐dimensional zig–zag chain, and these chains further connected by a Cu₂Br₂ unit, give a two‐dimensional framework on the bc‐plane. In the Cu₂Br₂ dimeric unit, the copper ions are four coordinated, thereby possessing a tetrahedral geometry; this proves to be an excellent heterogeneous catalyst for the aerobic homocoupling of arylboronic acids under mild reaction conditions. This method requires only 3 mol % of catalyst and it does not require any base or oxidant—compared to other conventional (Cu, Pd, Fe, and Au) catalysts—for the transformation of arylboronic acids in very good yields (98 %). The shape and size selectivity of the catalyst in the homocoupling was investigated. The use of the catalyst was further extended to the epoxidation of olefins. Moreover, the catalyst can be easily separated by simple filtration and reused efficiently up to 5 cycles without major loss of reactivity.     

In situ synthesis of mononuclear copper(II) complexes of the new tridentate ligand bis[(3,5‐dimethyl‐1H‐pyrazol‐1‐yl)methyl]amine

Two mononuclear copper complexes, {bis[(3,5‐dimethyl‐1H‐pyrazol‐1‐yl‐κN²)methyl]amine‐κN}(3,5‐dimethyl‐1H‐pyrazole‐κN²)(perchlorato‐κO)copper(II) perchlorate, [Cu(ClO₄)(C₅H₈N₂)(C₁₂H₁₉N₅)]ClO₄, (I), and {bis[(3,5‐dimethyl‐1H‐pyrazol‐1‐yl‐κN²)methyl]amine‐κN}bis(3,5‐dimethyl‐1H‐pyrazole‐κN²)copper(II) bis(hexafluoridophosphate), [Cu(C₅H₈N₂)₂(C₁₂H₁₉N₅)](PF₆)₂, (II), have been synthesized by the reactions of different copper salts with the tripodal ligand tris[(3,5‐dimethyl‐1H‐pyrazol‐1‐yl)methyl]amine (TDPA) in acetone–water solutions at room temperature. Single‐crystal X‐ray diffraction analysis revealed that they contain the new tridentate ligand bis[(3,5‐dimethyl‐1H‐pyrazol‐1‐yl)methyl]amine (BDPA), which cannot be obtained by normal organic reactions and has thus been captured in the solid state by in situ synthesis. The coordination of the Cu^II ion is distorted square pyramidal in (I) and distorted trigonal bipyramidal in (II). The new in situ generated tridentate BDPA ligand can act as a meridional or facial ligand during the process of coordination. The crystal structures of these two compounds are stabilized by classical hydrogen bonding as well as intricate nonclassical hydrogen‐bond interactions.     

Copper–Carbene Intermediates in the Copper‐Catalyzed Functionalization of OH Bonds

Copper–carbene [Tp^xCu?C(Ph)(CO₂Et)] and copper–diazo adducts [Tp^xCu{η¹‐N₂C(Ph)(CO₂Et)}] have been detected and characterized in the context of the catalytic functionalization of O?H bonds through carbene insertion by using N₂?C(Ph)(CO₂Et) as the carbene source. These are the first examples of these type of complexes in which the copper center bears a tridentate ligand and displays a tetrahedral geometry. The relevance of these complexes in the catalytic cycle has been assessed by NMR spectroscopy, and kinetic studies have demonstrated that the N‐bound diazo adduct is a dormant species and is not en route to the formation of the copper–carbene intermediate.     

Synthesis and Structure of [Tp*Rh{P(C7H7)3}] – Competition between the Ligands Tris(3,5‐dimethyl‐1‐pyrazolyl)borate (Tp*) and Tris(1‐cyclohepta‐2,4,6‐trienyl)phosphane. Proof of the κ2(N,B–H) Coordination Mode of the Tp* Ligand

Stepwise introduction of the potential tripod ligands tris(3,5‐dimethyl‐1‐pyrazolyl)borate (Tp*) and tris(1‐cyclohepta‐2,4,6‐trienyl)phosphane into the coordination sphere of rhodium(I) leads mainly to [Tp*Rh{P(C₇H₇)₃}] ( 4 ), in which Tp* is linked to the rhodium through a single pyrazolyl group and a non‐linear B–H–Rh bridge. This is the novel, now firmly established coordination mode κ²(N,B–H). The phosphane ligand is coordinated through one Rh–P and two Rh‐olefin bonds. Important structural features determined for the crystalline state of 4 are retained in solution, as shown by the ¹H, ¹¹B, ¹³C, ³¹P and ¹⁰³Rh NMR spectra.     

A Water‐Soluble Copper–Polypyridine Complex as a Homogeneous Catalyst for both Photo‐Induced and Electrocatalytic O2 Evolution

The water‐soluble polypyridine copper complex [Cu(F₃TPA)(ClO₄)₂] [ 1 ; F₃TPA=tris(2‐fluoro‐6‐pyridylmethyl)amine] catalyzes water oxidation in a pH 8.5 borate buffer at a relatively low overpotential of 610 mV. Assisted by photosensitizer and an electron acceptor, 1 also exhibits activity as a homogeneous catalyst for photo‐induced O₂ evolution with a maximum turnover frequency (TOF) of (1.58±0.03)×10^?1 s^?1 and a maximum turnover number (TON) of 11.61±0.23. In comparison, the reference [Cu(TPA)(ClO₄)₂] [TPA=tris(2‐pyridylmethyl)amine] displayed almost no activity under either set of conditions, implying the crucial role of the ligand in determining the behavior of the catalyst. Experimental evidence indicate the molecular catalytic nature of 1 , leading to a potentially practical strategy to apply the copper complex in a photoelectrochemical device for water oxidation.     

Conjugated Copper–Catecholate Framework Electrodes for Efficient Energy Storage

A conjugated copper(II) catecholate based metal–organic framework (namely Cu‐DBC) was prepared using a D₂‐symmetric redox‐active ligand in a copper bis(dihydroxy) coordination geometry. The π‐d conjugated framework exhibits typical semiconducting behavior with a high electrical conductivity of ca. 1.0 S m^?1 at room temperature. Benefiting from the good electrical conductivity and the excellent redox reversibility of both ligand and copper centers, Cu‐DBC electrode features superior capacitor performances with gravimetric capacitance up to 479 F g^?1 at a discharge rate of 0.2 A g^?1. Moreover, the symmetric solid‐state supercapacitor of Cu‐DBC exhibits high areal (879 mF cm^?2) and volumetric (22 F cm^?3) capacitances, as well as good rate capability. These metrics are superior to most reported MOF‐based supercapacitors, demonstrating promising applications in energy‐storage devices.     

5‐n‐Butylpyridine‐2‐carboxylate–copper(II) and –iron(III) complexes

In trans‐bis(5‐n‐butyl­pyridine‐2‐carboxyl­ato‐κ²N,O)­bis­(methanol‐κO)copper(II), [Cu(C₁₀H₁₂NO₂)₂(CH₄O)₂], the Cu atom lies on a centre of symmetry and has a distorted octahedral coordination. The Cu—O(methanol) bond length in the axial direction is 2.596 (3) Å, which is much longer than the Cu—­O(carboxylate) and Cu—N distances in the equatorial plane [1.952 (2) and 1.977 (2) Å, respectively]. In mer‐tris(5‐n‐bu­tyl­pyridine‐2‐carboxyl­ato‐κ²N,O)­iron(III), [Fe(C₁₀H₁₂NO₂)₃], the Fe atom also has a distorted octahedral geometry, with Fe—O and Fe—N bond‐length ranges of 1.949 (4)–1.970 (4) and 2.116 (5)–2.161 (5) Å, respectively. Both crystals are stabilized by stacking interactions of the 5‐n‐butyl­pyridine‐2‐carboxyl­ate ligand, although hydrogen bonds also contribute to the stabilization of the copper(II) complex.     

Constructing mixed‐metal coordination polymers from copper(II)–pyridinedicarboxylate metalloligands

In the mixed‐metal complex catena‐poly[bis[diaquasilver(I)] [bis[aquacopper(II)]‐μ₃‐pyridine‐2,5‐dicarboxylato‐2′:1:1′κ⁵N,O²:O⁵:O⁵,O^5′‐μ‐pyridine‐2,5‐dicarboxylato‐2:1κ⁴N,O²:O⁵,O^5′‐disilver(I)‐μ₃‐pyridine‐2,5‐dicarboxylato‐1:1′:2′′κ⁵O⁵,O^5′:O⁵:N,O²‐μ‐pyridine‐2,5‐dicarboxylato‐1′:2′′′κ⁴O⁵,O^5′:N,O²] hexahydrate], {[Ag(H₂O)₂][AgCu(C₇H₃NO₄)₂(H₂O)]·3H₂O}_n, a square‐pyramidal Cu^II center is coordinated by two N atoms and two O atoms from two pyridine‐2,5‐dicarboxylate (2,5‐pydc) ligands and a water molecule, forming a [Cu(2,5‐pydc)₂(H₂O)]²⁻ metalloligand. One Ag^I center is coordinated by five O atoms from three 2,5‐pydc ligands and, as a result, the [Cu(2,5‐pydc)₂(H₂O)]²⁻ metalloligands act as linkers in a unique μ₃‐mode connecting Ag^I centers into a one‐dimensional anionic double chain along the [101] direction. The other Ag^I center is coordinated by two water molecules, forming an [Ag(H₂O)₂]⁺ cation. Four adjacent Ag^I centers are associated by Ag...Ag interactions [3.126 (1) and 3.118 (1) Å], producing a Z‐shaped Ag₄ unit along the [010] direction and connecting the anionic chains into a two‐dimensional layer structure. This study offers information for engineering mixed‐metal complexes based on copper(II)–pyridinedicarboxylate metalloligands.     

Highly Luminescent Inks: Aggregation‐Induced Emission of Copper–Iodine Hybrid Clusters

Aggregation‐induced emission (AIE) is an attractive phenomenon in which materials display strong luminescence in the aggregated solid states rather than in the conventional dissolved molecular states. However, highly luminescent inks based on AIE are hard to be obtained because of the difficulty in finely controlling the crystallinity of AIE materials at nanoscale. Herein, we report the preparation of highly luminescent inks via oil‐in‐water microemulsion induced aggregation of Cu–I hybrid clusters based on the highly soluble copper iodide‐tris(3‐methylphenyl)phosphine (Cu₄I₄(P‐(m‐Tol)₃)₄) hybrid. Furthermore, we can synthesize a series of AIE inks with different light‐emission colors to cover the whole visible spectrum range via a facile ligand exchange processes. The assemblies of Cu–I hybrid clusters with AIE characteristics will pave the way to fabricate low‐cost highly luminescent inks.     

Remarkable Structural and Electronic Features of the Complex Formed by Trimeric Copper Pyrazolate with Pentaphosphaferrocene

According to spectroscopic (NMR, IR, UV/Vis) study, the interaction of pentaphosphaferrocene [Cp*Fe(η⁵‐P₅)] with trimeric copper pyrazolate [(Cu{3,5‐(CF₃)₂Pz})₃] yields a new compound that is astonishingly stable in solution. Single‐crystal X‐ray analysis reveals unprecedented structural changes in the interacting molecules and the unique type of coordination [Cp*Fe(μ₃‐η⁵:η²,η²‐P₅){Cu(3,5‐(CF₃)₂Pz)}₃]. As a result of the 90° macrocycle folding, the copper atoms are able to behave both as a Lewis acid and as a Lewis base in the interaction with the cyclo‐P₅ ligand.     

Towards a Molecular Understanding of Cation–Anion Interactions—Probing the Electronic Structure of Imidazolium Ionic Liquids by NMR Spectroscopy,X‐ray Photoelectron Spectroscopy and Theoretical Calculations

Ten [C₈C₁Im]⁺ (1‐methyl‐3‐octylimidazolium)‐based ionic liquids with anions Cl^?, Br^?, I^?, [NO₃]^?, [BF₄]^?, [TfO]^?, [PF₆]^?, [Tf₂N]^?, [Pf₂N]^?, and [FAP]^? (TfO=trifluoromethylsulfonate, Tf₂N=bis(trifluoromethylsulfonyl)imide, Pf₂N=bis(pentafluoroethylsulfonyl)imide, FAP=tris(pentafluoroethyl)trifluorophosphate) and two [C₈C₁C₁Im]⁺ (1,2‐dimethyl‐3‐octylimidazolium)‐based ionic liquids with anions Br^? and [Tf₂N]^? were investigated by using X‐ray photoelectron spectroscopy (XPS), NMR spectroscopy and theoretical calculations. While ¹H NMR spectroscopy is found to probe very specifically the strongest hydrogen‐bond interaction between the hydrogen attached to the C² position and the anion, a comparative XPS study provides first direct experimental evidence for cation–anion charge‐transfer phenomena in ionic liquids as a function of the ionic liquid’s anion. These charge‐transfer effects are found to be surprisingly similar for [C₈C₁Im]⁺ and [C₈C₁C₁Im]⁺ salts of the same anion, which in combination with theoretical calculations leads to the conclusion that hydrogen bonding and charge transfer occur independently from each other, but are both more pronounced for small and more strongly coordinating anions, and are greatly reduced in the case of large and weakly coordinating anions.     

Regioselective formation of 2,5-disubstituted oxazoles via copper(i)-catalyzed cycloaddition of acyl azides and 1-alkynes

The reaction of 1-alkynes with acyl azides in the presence of [Tpm(*,Br)Cu(NCMe)]BF(4) [Tpm(*,Br) = tris(3,5-dimethyl-4-bromopyrazolyl)methane] as the catalyst provides 2,5-oxazoles in moderate to high yields. This is a novel transformation of the CuAAC type that constitutes a significant variation of the commonly observed [3 + 2] cycloaddition reaction to yield 1,2,3-triazoles.     

A Boron‐Fluorinated Tris(pyrazolyl)borate Ligand (FTp*) and Its Mono‐ and Dinuclear Copper Complexes [Cu(FTp*)2] and [Cu2(FTp*)2]: Synthesis,Structures, and DFT Calculations

Reaction of [Si(3,5‐Me₂pz)₄] ( 1 ) with [Cu(MeCN)₄][BF₄] ( 2 ) gave the mono‐ and dinuclear copper complexes [Cu₂(^FTp*)₂] ( 3 ) and [Cu(^FTp*)₂] ( 4 ). Both complexes contain the so‐far unprecedented boron‐fluorinated ^FTp* ligand ([FB(3,5‐Me₂pz)₃]^? with pz=pyrazolyl) originating from 1 , acting as a pyrazolyl transfer reagent, and the [BF₄]^? counter anion of 2 , serving as the source of the {BF} entity. The solid‐state structures as well as the NMR and EPR spectroscopic characteristics of the complexes were elaborated. Pulsed gradient spin echo (PGSE) experiments revealed that 3 retains (almost entirely) its dimeric structure in benzene, whereas dimer cleavage and formation of acetonitrile adducts, presumably [Cu(^FTp*)(MeCN)], is observed in acetonitrile. The short Cu???Cu distance of 269.16 pm in the solid‐state is predicted by DFT calculations to be dictated by dispersion interactions between all atoms in the complex (the Cu?Cu dispersion contribution itself is only very small). As revealed by cyclic voltammetry studies, 3 shows an irreversible (almost quasi‐reversible at higher scan rates) oxidation process centred at E^pa=?0.23 V (E⁰_1/2=?0.27 V) (vs. Fc/Fc⁺). Oxidation reactions on a preparative scale with one equivalent of the ferrocenium salt [Fc][BF₄] (very slow reaction) or air (fast reaction) furnished blue crystals of the mononuclear copper(II) complex [Cu(^FTp*)₂] ( 4 ). As expected for a Jahn–Teller‐active system, the coordination sphere around copper(II) is strongly distorted towards a stretched octahedron, in accordance with EPR spectroscopic findings.     

Synthesis,structure and photocatalytic degradation of organic dyes of a copper(II) metal–organic framework (Cu–MOF) with a 4‐coordinated three‐dimensional CdSO4 topology

Metal–organic frameworks (MOFs) have attracted much interest in the fields of gas separation and storage, catalysis synthesis, nonlinear optics, sensors, luminescence, magnetism, photocatalysis gradation and crystal engineering because of their diverse properties and intriguing topologies. A Cu–MOF, namely poly[[(μ₂‐succinato‐κ²O:O′){μ₂‐tris[4‐(1,2,4‐triazol‐1‐yl)phenyl]amine‐κ²N:N′}copper(II)] dihydrate], {[Cu(C₄H₄O₄)(C₂₄H₁₈N₁₀)]·2H₂O}_n or {[Cu(suc)(ttpa)]·2H₂O}_n, (I), was synthesized by the hydrothermal method using tris[4‐(1,2,4‐triazol‐1‐yl)phenyl]amine (ttpa) and succinate (suc^2?), and characterized by IR, powder X‐ray diffraction (PXRD), luminescence, optical band gap and valence band X‐ray photoelectron spectroscopy (VB XPS). Cu–MOF (I) shows a twofold interpenetrating 4‐coordinated three‐dimensional CdSO₄ topology with point symbol {6⁵·8}. It presents good photocatalytic degradation of methylene blue (MB) and rhodamine B (RhB) under visible‐light irradiation. A photocatalytic mechanism was proposed and confirmed.     

Crystal Structures,Magnetic Properties and Catecholase‐Like Activities of μ‐Alkoxo‐μ‐Carboxylato Double Bridged Dinuclear and Tetranuclear Copper(II) Complexes

One μ‐alkoxo‐μ‐carboxylato bridged dinuclear copper(II) complex, [Cu₂(L¹)(μ‐C₆H₅CO₂)] ( 1 )(H₃L¹ = 1,3‐bis(salicylideneamino)‐2‐propanol)), and two μ‐alkoxo‐μ‐dicarboxylato doubly‐bridged tetranuclear copper(II) complexes, [Cu₄(L¹)₂(μ‐C₈H₁₀O₄)(DMF)₂]·H₂O ( 2 ) and [Cu₄(L²)₂(μ‐C₅H₆O₄]·2H₂O·2CH₃CN ( 3 ) (H₃L² = 1,3‐bis(5‐bromo‐salicylideneamino)‐2‐propanol)) have been prepared and characterized. The single crystal X‐ray analysis shows that the structure of complex 1 is dimeric with two adjacent copper(II) atoms bridged by μ‐alkoxo‐μ‐carboxylato ligands where the Cu···Cu distances and Cu‐O(alkoxo)‐Cu angles are 3.5 11 Å and 132.8°, respectively. Complexes 2 and 3 consist of a μ‐alkoxo‐μ‐dicarboxylato doubly‐bridged tetranuclear Cu(II) complex with mean Cu‐Cu distances and Cu‐O‐Cu angles of 3.092 Å and 104.2° for 2 and 3.486 Å and 129.9° for 3 , respectively. Magnetic measurements reveal that 1 is strong antiferromagnetically coupled with 2J =‐210 cm^?1 while 2 and 3 exhibit ferromagnetic coupling with 2J = 126 cm^?1 and 82 cm^?1 (averaged), respectively. The 2J values of 1–3 are correlated to dihedral angles and the Cu‐O‐Cu angles. Dependence of the pH at 25 °C on the reaction rate of oxidation of 3,5‐di‐tert‐butylcatechol (3,5‐DTBC) to the corresponding quinone (3,5‐DTBQ) catalyzed by 1–3 was studied. Complexes 1–3 exhibit catecholase‐like active at above pH 8 and 25 °C for oxidation of 3,5‐di‐tert‐butylcatechol.     

Two 2,5‐bis(2‐pyridinyl)‐1,3,4‐oxa­diazo­le–metal complexes (M = Cu and Ni)

The reaction of the diazine ligand 3,5‐bis(2‐pyridinyl)‐1,3,4‐oxa­diazole (pod, C₁₂H₈N₄O), with Cu(CF₃SO₃)₂ or Ni(ClO₄)₂ afforded the title complexes di­aqua­bis­[3,5‐bis(2‐pyridinyl)‐1,3,4‐oxa­diazole‐N²,N³]copper(II) bis­(tri­fluoro­methane­sul­fon­ate), [Cu(pod)₂(H₂O)₂](CF₃SO₃)₂, and di­aqua­bis­[3,5‐bis(2‐pyridinyl)‐1,3,4‐oxa­diazo­le‐N²,N³]­nickel(II) diperchlorate, [Ni(pod)₂(H₂O)₂](ClO₄)₂. Both complexes present a crystallographically centrosymmetric mononuclear cation structure which consists of a six‐coordinated Cu^II or Ni^II ion with two pod mol­ecules acting as bidentate ligands and two axially coordinated water mol­ecules.     

Carbonyl–carbonyl and carbonyl–π interactions as directing motifs in the supramolecular structure of carbonyl(3‐oxopenta‐1,4‐diene‐1,5‐diyl)[tris(3,5‐dimethyl‐1H‐pyrazol‐1‐yl‐κN2)methane]iridium(III) trifluoromethanesulfonate

In the title complex salt, [Ir(C₅H₄O)(C₁₆H₂₂N₆)(CO)](CF₃O₃S), the Ir^III centre adopts a distorted octahedral geometry with a facial coordination of the tris(3,5‐dimethyl‐1H‐pyrazol‐1‐yl)methane ligand. The C—C distances of the iridacycle are in agreement with its iridacyclohexa‐2,5‐dien‐4‐one nature, which presents a nonsymmetric boat‐like conformation with the C—Ir—C vertex more bent than the C—C(=O)—C vertex. The supramolecular architecture is mainly directed by CO...CO and CO...π and Csp³—H...O interactions, the arrangement of which depends on the anion.     

Effect of Polycarboxylate Coligands from Linear to V‐shaped CuII Coordination Polymers Based on a Rigid Tripodal Ligand

The layered Cu^II coordination polymer {[Cu(tib)₂(H₂O)₂](NO₃)₂} ( 1 ) based on the rigid tripodal 1,3,5‐tris(1‐imidazolyl)benzene (tib) ligand was synthesized by hydrothermal methods. By introducing different polycarboxylate coligands from linear 4,4′‐biphthalic acid (H₄L¹) to V‐shaped thiophene‐2,5‐dicarboxylic acid (H₂L²), two new copper(II) compounds were obtained, namely, {Cu(tib)(H₂L¹)(H₂O) · 3H₂O} ( 2 ) and {Cu(tib)(L²) · 3H₂O} ( 3 ). X‐ray diffraction analyses reveal that compound 2 displays a hydrogen‐bonded three‐dimensional (3D) supramolecular structure, in which protonated {H₂L¹}^2– ligands occupy some coordination sites around the metal atoms to form one‐dimensional (1D) chain by blocking the formation of two‐dimensional (2D) Cu‐tib layer as in compound 1 . Interestingly, compound 3 features a rare twofold interpenetrating binodal seh ‐3,5‐P4₃2₁2 topological network by synergistic effect of V‐shaped carboxylate group and functionally complementary N‐donor ligand. These compounds were characterized by elemental analyses, thermogravinetric analyses, and photoluminescent spectroscopy.     

X‐ray structure and density functional theory studies of an unexpected product: trans‐bis{2‐[(2‐cyanoethyl)iminomethyl]phenolato}copper(II)

The title compound, [Cu(C₁₀H₉N₂O)₂] or [Cu^II(CYMB)₂], (I), was obtained in an attempt to reduce trans‐bis(2‐{[3,5‐bis(trifluoromethyl)phenyl]iminomethyl}phenolato)copper(II), [Cu(TIMB)₂], (II), with bis(pentamethylcyclopentadienyl)cobalt(II) [decamethylcobaltocene, Cp*₂Co, (III)]. The molecular structure of (I) has the Cu^II centre located on an inversion centre of the C2/c space group. A density functional theory (DFT) analysis at the B3LYP/Lanl2dz(CuF);6‐31G**(CHNO) level performed in order to optimize the structures of the free ligands CYMB⁻ and TIMB⁻, and the metal complexes [Cu^I/II(CYMB)₂]^−/0 and [Cu^I/II(TIMB)₂]^−/0, reproduced well the X‐ray diffraction structure and allowed us to infer the insertion of the cyanomethide anion on the 3,5‐bis(trifluoromethyl)phenyl system from an evaluation of the Mulliken atomic charges and the electronic energies.