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[Display omitted] The PdAg/α-Al 2 O 3 catalyst with an egg-shell distribution of single-atom alloy (SAA) Pd 1 Ag nanoparticles was obtained using the complex PdAg 2 (OAc) 4 (HOAc) 4 as a precursor and characterized by FESEM-EDS, XPS, and DRIFTS CO analysis. The egg-shell Pd 1 Ag SAA catalyst demonstrated superior selectivity in the hydrogenation of acetylene in acetylene–ethylene feed. [ABSTRACT FROM AUTHOR]

• Synthesis of Cu(I)/Fe(II) heterobimetallic complexes. • Quasireversible redox behaviour is observed for all heterobimetallic complexes. • Complexes exhibit red emission in dichloromethane solution. • Complex 4 worked as effective catalyst for C-N coupling reaction. A new series of heterobimetallic complexes of the type [Cu(L)(PPh 3) 2 ]X (1–4) [where L = trans-4-(ferrocenylideneamino)-1,5-dimethyl-2-phenyl-1H-pyrazol-3(2H)-one; PPh 3 = triphenylphosphine, X = NO 3 −(1), ClO 4 − (2), BF 4 − (3) , PF 6 − (4)] were prepared by reaction of L with [Cu(MeCN) 2 (PPh 3) 2 ]X and characterized by elemental analysis, FTIR, 1H NMR, 31P NMR and UV–visible spectral studies. The thermal stability of (1–4) has been investigated by using thermogravimetric analysis (TGA). X-ray powder diffraction of the representative complex 1 used to clarify the crystal structure of the complex. The electrochemical behaviour of complexes (1–4) displayed quasireversible redox behaviour corresponding to Cu(I)/Cu(II) and Fe(II)/Fe(III) couples. All complexes show red emission as a result of ligand-ligand charge transfer (LLCT) and metal-ligand charge transfer (MLCT) or admixture of them. The catalytic efficiency of the complexes (1–4) was tested and it was found that the complex 4 worked as an effective catalyst for the C-N coupling reaction of aromatic amines and aryl halides. [Display omitted] [ABSTRACT FROM AUTHOR]

• [Ga-Rh] complex exhibits excellent catalytic activity in nitrile hydrosilylation. • Reaction activity is controlled by the distortion energy of rate-determining state. • Phenylacetonitrile tends to insert into Rh-H bond than Rh-Si bond. Transition metals catalyzed hydrosilylation reaction is of significant values in organic synthesis. Herein the detailed mechanisms of the phenylacetonitrile hydrosilylation catalyzed by bimetallic [E-Rh] (E =Al, Ga, In) catalysts, as well as the RhCl(PPh 3) 3 monometallic catalyst, were investigated by DFT calculations. The electronic structure analysis indicates that the different atomic contributions of the Rh atom in E-Rh bond result in the polarity variations of the metal-metal bonds and different catalytic activities. The whole catalyzed cycle involves five processes: the formation of rhodium hydride complex, activation of H 2 SiMe 2 , insertion of phenylacetonitrile, reductive elimination, and isomerization. The reaction activities of [E-Rh] (E =Al, Ga, In) decrease successively, which is in agreement with the atomic contributions of Rh in three catalysts. DI analysis provides the evidence that the catalytic activity is controlled by the distortion energy of rate-determining state. QTAIM analysis shows the transformation of the Cl atom between two metal atoms, providing a clear description for structural changes in catalytic cycle. The detailed mechanisms and chemoselectivity of the nitrile hydrosilylation catalyzed by the heterobimetallic [E-Rh] (E =Al, Ga, In) catalysts were investigated by DFT study. The activity sequence of E =Ga>>Al and In has been explained. [Display omitted] [ABSTRACT FROM AUTHOR]

Two mononuclear luminescent tricyanoruthenium(II) compounds have been prepared. The coordination geometry around the Ru(II) centers are readily changed from fac- to mer -configuration upon coordination with Zn2+ complexes. Upon loading 1b onto nano SiO 2 , the luminescence of 1b@SiO 2 is remarkably enhanced and the luminescent detection limit can reach 0.1 µM. [Display omitted] • Two mononuclear luminescent tricyanoruthenium(II) compounds were obtained. • Facile fac- to mer-configuration transformation of Ru(II) centers upon coordination with Zn2+ complexes. • These Ru(II) complexes display strong solvatochromism. • The luminescence of 1b@SiO 2 is remarkably enhanced, possessing potential application as chemical tracer for water flooding. Two mononuclear tricyanoruthenium(II) compounds fac -(PPh 4)[RuII(dpq)(CN) 3 (PPh 3)] (1a), fac -(PPh 4)[RuII(Ph 2 Phen)(CN) 3 (PPh 3)] (2a) have been prepared from the reactions of (PPh 4) 2 [RuII(PPh 3) 2 (CN) 4 ] with pyrazino[2,3-f][1,10]phenanthroline (dpq) and 4,7-diphenyl-1,10-phenanthroline (Ph 2 Phen) in DMF, respectively. Metathesis of 1a/2a with excess NaPF 6 in MeOH afforded fac -Na[RuII(dpq)(CN) 3 (PPh 3)] (1b) and fac -Na[RuII(Ph 2 Phen)(CN) 3 (PPh 3)] (2b), respectively where the coordination geometries around the Ru(II) centers are retained. However, treatment of 1a with [Zn(cyclam)]Cl 2 or [Zn(cyclen)]Cl 2 afforded the trinuclear heterobimetallic complexes [Zn(cyclam){ mer -RuII(dpq)(CN) 3 (PPh 3)} 2 ] (3) and mer -[RuII(dpq)(CN) 3 (PPh 3)][Zn(cyclen){ mer -RuII(dpq)(CN) 3 (PPh 3)}] (4), respectively. The crystal structures of 1a, 1b, 2a, 3, and 4 have been determined by X-ray crystallography. It is clearly shown that the coordination geometries of Ru(II) centers are changed from fac - to mer -configuration upon coordination with Zn2+ complexes. It is noteworthy that in 4 the coordination geometry in the anionic Ru moiety is also changed, although it is not linked to the Zn2+ moiety. The luminescence properties of these compounds have been investigated in detail. Both 1a and 1b exhibit strong solvatochromism as those related complexes. 1b is soluble in H 2 O and the luminescent detection limit can reach 0.01 mM in H 2 O. Upon loading 1b onto nano SiO 2 , the luminescence of 1b@SiO 2 is remarkably enhanced and the luminescent detection limit can reach 0.1 µM. [ABSTRACT FROM AUTHOR]

• A 50-electron triruthenium μ 3 -methylidyne complex was synthesized. • The 50-electron configuration is stabilized by the elongation of the Ru−Ru distance. • The 50-electron nature causes degradation of the cluster skeleton. • The unsubstituted μ -methylidyne ligand is the key to the trinuclear skeleton. A chloride salt of cationic triruthenium complex containing a μ 3 -methylidyne ligand, [{Cp*Ru(μ -Cl)} 3 (μ 3 CH)]+ (4 ; Cp* = η 5-C 5 Me 5)), was synthesized by the reaction of diruthenium tetrahydrido complex [Cp*Ru(μ -H) 4 RuCp*] (1) with chloroform in 91% yield. Although 4 contains a 50-electron configuration, an X-ray diffraction study of a tetraphenylborate salt of 4 demonstrated that 4 has a closed-triangular triruthenium skeleton with a Ru−Ru distance of ca. 2.87 Å, which is considerably longer than the Cl-bridged Ru−Ru distance in the related 48-electron μ 3 -methylidyne complex, [(Cp*Ru) 3 (μ 3 CH)(μ -Cl) 2 (μ -H)]+ (5 ; 2.757(1) Å). Complex 4 was also obtained by the reaction of triruthenium pentahydrido complex [{Cp*Ru(μ -H)} 3 (μ 3 H) 2 ] (2) with CHCl 3 , and crossover experiments using 2 and [{CpEtRu(μ -H)} 3 (μ 3 H) 2 ] (2-Et 3 ; CpEt = η 5-C 5 EtMe 4) demonstrated that the cluster skeleton of 2 was broken during the reaction. These results are contrasted with the exclusive formation of dinuclear μ -chloromethylidyne complex, [(Cp*RuCl) 2 (μ -CCl)(μ -Cl)] (3), by the reaction of 1 with CCl 4 , and the number of nuclei of the product is suggested to be determined by the substituent at the methylidyne carbon. Although a triruthenium complex was not formed by the reaction of 3 with [Cp*RuCl] 4 , a heterobimetallic trinuclear μ 3 -methylidyne complex, [(Cp*Ru) 2 (Cp*Ir)(μ 3 CH)(μ -Cl)(μ -H) 2 ] (9) was obtained by the reaction of 3 with [Cp*IrH 4 ] along with substitution of the chloromethylidyne ligand by a hydride. [Display omitted] [ABSTRACT FROM AUTHOR]

Three polymeric heterobimetallic {Pt,M} lantern chains have been synthesized with DABCO, along with the discrete molecular analog of each with quinuclidine. Measurements of the temperature dependence of the magnetic susceptibility of M = Co and Ni chains reveal antiferromagnetic exchange coupling between the 3 d metal centers with J = −10 cm−1 for the Co-containing compound and J = −32 cm−1 between Ni centers in the other, both of which access the Pt...Pt metallophilic interactions. [Display omitted] A small series of polymeric heterobimetallic {Pt,M} lantern complexes of the form [PtM(SAc) 4 DABCO] ∞ (SAc = thioacetate, DABCO = 1,4-diazabicyclo [2,2,2] octane; M = Co (1), Ni (2), Zn (3)) has been synthesized, along with the discrete molecular analog of each polymer formed by replacing DABCO with quinuclidine (4 – 6). All compounds except 3 have been structurally characterized by single-crystal X-ray diffraction. Compound 1 shows a metallophilic Pt...Pt interaction of 3.1204(4) Å, while in 2 the same interaction is even shorter at 3.0944(10) Å. The electronic spectra of all compounds have been measured, which show d-d transitions of the 3 d metal, Pt LMCT bands, and metal–metal charge transfer bands. Measurements of the temperature dependence of the magnetic susceptibility of 1 and 2 reveal antiferromagnetic exchange coupling between the 3 d metal centers with J = −10 cm−1 for Co-containing 1 and J = −32 cm−1 between Ni centers for 2 , both of which access the Pt...Pt metallophilic interactions. [ABSTRACT FROM AUTHOR]

The synthesis and electrochemical properties of nickel, palladium and platinum mesoionic carbenes complexes is presented and investigated. The study shows that in such mono-MIC systems, ligand oxidation is favored over metal oxidation giving access to unique ligand radical complexes, supported by a N -heterocyclic / mesoionic carbene moiety. [Display omitted] • Synthesis of an isostructural series of group 10 MIC complexes. • Investigation of electrochemical properties and the structural, crystalline isolation of all oxidized products. • EPR spectroscopy of all compounds and theoretical calculations on the electronic structure. We present the synthesis of an isostructural series of group 10 mesoionic carbene complexes with the general formula [M(MIC)Py] (with M = Ni (1), Pd (2) and Pt (3), Py = pyridine and MIC = bis-phenolate triazolylidene). Their electrochemical properties are investigated, revealing two quasi-reversible oxidations for all compounds, while no reductions are observed. Isolation of the oxidized species has been achieved using either silver triflate or nitrosonium tetrafluoroborate for the nickel and the platinum complex yielding the corresponding mono-cationic complexes [1] X and [3] X (X = OTf or BF 4). For the palladium complex, oxidation reactions yielded different products 4 and 5 in which the pyridine and/or the phenol(oxy) donors were found to be labile compared to Ni and Pt. Additionally, for Pt the electron transfer reaction was found to be quite slow and short reaction times led to the isolation of an unusual heterobimetallic silver-platinum complex 6. The location of the redox event has been investigated using EPR spectroscopy and computational methods, which suggest, that the oxidation is mostly centered on one of the phenolate anchors. [ABSTRACT FROM AUTHOR]

Bimetallic complexe Ni-Co-pzdc and its derivatives were prepared by a simple method, both were used to catalyze ammonium perchlorate to improve its thermal decomposition performance, and the experimental results showed that all had good catalytic effects, among which, Ni-Co-pzdc derivatives had a more excellent catalytic effect, which made the high-temperature thermal decomposition temperature of AP lowered by 136 ℃ and the activation energy lowered by 128.21 kJ·mol−1. [Display omitted] • A novel bimetallic complex was prepared using 2,3-pyrazinedicarboxylic acid as a ligand and Ni and Co as the center metals. • Used the complex as a sacrificial template to obtain its derivatives as N-doped NiCoO 2 composite carbon materials. • The bimetallic oxide NiCoO 2 has a synergistic effect of metal ions, and the N-doped carbon material can accelerate the transfer of electrons and thus enhance the effect of catalytic AP, so the resulting derivatives have excellent catalytic properties. The addition of a catalyst to ammonium perchlorate (AP) can effectively improve its thermal decomposition properties. The heterobimetallic complex Ni-Co-pzdc (2,3-pyrazinedicarboxylic acid) was synthesized via in situ substitution, and the N-doped Ni-Co-pzdc derivative was prepared by using it as a sacrificial template. A series of characterization tools were used to investigate the morphological and structural features of the resulting materials, and the thermal decomposition behaviors of the two products were investigated by homogeneous mixing with AP, respectively, and the activation energies were calculated by using Kissinger, Kissinger-Akahira-Sunose (KAS), and Flynn-Wall-Ozawa (FWO), and the results showed that both substances possessed excellent catalytic activities. [ABSTRACT FROM AUTHOR]

• Four novel heterobimetallic Fe(II)-Cu(I) complexes based on dppf and dialkyldithiophosphate ligands were prepared. • Full characterization of the complexes was carried out using multinuclear NMR spectroscopy and single crystal X-ray crystallography studies. • These novel complexes proved to be efficient anticancer agents, degree of which depend on the nature of substituents on dialkyldithiophosphate ligands. • To calculate electronic structures, a density functional theory analysis of the Fe(II)-Cu(I) complexes were carried out. Heterobimetallic complexes [(dppf)CuSP(S)(OiPr) 2 ] (1), [(dppf)CuSP(S)(OEt) 2 ] (2), [(dppf)CuSP(S)(OCy) 2 ] (3) and [(dppf)CuS 2 H 2 B(mt) 2 ] (4), supported with sulfur donors from the family of dialkyldithiophosphate, SP(S)(OR) 2 (R = iPr, Et, Cy) and borate ligands, (S) 2 H 2 B(mt) 2 , were synthesized in one pot by the reaction of 1,1′-Bis(diphenylphosphino)ferrocene (dppf) with [Cu(CH 3 CN) 4 ]BF 4 and subsequent addition of the chelating sulfur donor ligands at room temperature in an overall moderate yield. 1 - 4 were characterized using a combination of 1H, 13C{1H}, 31P{1H} NMR, IR spectroscopy techniques, and single crystal X-ray diffraction. Crystal structure analysis revealed that Cu(I) centers in 1 - 4 adopt a distorted tetrahedral geometry. The borate ligand in 4 adopts a κ3-S,S,H mode in the solid state. A density functional theory geometry optimization calculation was used to extract further structural and electronic information about 1 - 4. To investigate the possible cytotoxicity of 1 - 4 , in vitro cellular tests were carried out on the human cancerous breast cell line MCF-7. The antibacterial activities of complexes 1 and 4 were screened against gram-positive Staphylococcus aureus PTCC 1112 and gram-negative Escherichia col i PTCC 1330. [Display omitted] [ABSTRACT FROM AUTHOR]

• A serial of new cyanide-bridged heterobimetallic CrIII/I CuII complexes. • Different structure types from 0D cluster, 1D chain to 2D network. • The ferro- or antiferromagnetic coupling through cyanide bridge. • The effects on the structure type from the building block and the preparation method. One cyanide-bridged heterometallic achiral complex and two pairs of enantiomers {[Cu(Chxn) 2 Cr(bpb)(CN) 2 ]ClO 4 }·CH 3 OH·H 2 O (1), {[Cu(S,S/R,R -Chxn) 2 Cr(CN) 5 (NO)] 2 [Cu(S,S/R,R -Chxn) 2 (H 2 O) 2 ]} n ·3nH 2 O (2, 3) {[Cu(S,S/R,R -Chxn) 2 ] 3 [Cr(CN) 5 (NO)] 2 } n ·5nH 2 O (4, 5). (bpb = bis(2-benzimidazolyl)pyridine dianion, Chxn = 1,2-diaminocyclohexane) have been assembled from two cyano containing Cr(I) or Cr(III) building blocks, K[Cr(bpb)(CN) 2 ] and K 3 [Cr(CN) 5 (NO)], and racem ic or chiral copper(II) compounds under the different reaction conditions. The complexes have been characterized by element analysis, IR spectra, the circular dichroism (CD) spectrum, powder and single crystal X-ray diffraction. X-ray structural analyses revealed that the divers structure types of complexes 1–5 ranging from discrete polynuclear entity (1), 1D coordination polymer (CP) anionic chain (2, 3) to neutral 2D CP network (4, 5), indicating clearly the important role of the building block and preparation method on tuning the structure of the target cyanide-bridged complexes. The magnetic properties for the reported complexes have been experimentally studied and theoretically simulated, disclosing the ferromagnetic coupling between the Cr(III) ion and Cu(II) ion and the rare antiferromagnetic interaction within Cr(I Cu(II) unit through the cyanide bridge, respectively. Furthermore, the magnetic coupling nature has been analyzed based-on the magneto-structural correlation. A serial of cyanide-bridged heterometallic achiral complexes structural ranging from polynuclear entities, 1D anionic chain to neutral 2D network have been assembled from two cyano containing Cr(I) or Cr(III) building blocks and racemic or chiral copper(II) compounds under the different reaction conditions, indicating clearly the important role of the building block and preparation method on tuning the structure of the target cyanide-bridged complexes. The magnetic properties for the reported complexes have been experimentally studied and theoretically simulated, disclosing the ferromagnetic coupling between the Cr(III) ion and Cu(II) ion and the rare antiferromagnetic interaction within Cr(I) Cu(II) unit through the cyanide bridge, respectively. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • The biologically potent monometallic and heterobimetallic complexes of Ni(II) were synthesized. • All the synthesized complexes were characterized by various spectroscopic techniques like UV, FTIR, Mass, 1H NMR, 13C NMR and Powder X-ray diffraction studies. • Geometry of the synthesized complexes was also supported by Density functional theory calculations. • Heterobimetallic complexes showed good antimicrobial activity against a number of pathogenic fungi and bacteria. The newly designed trinuclear heterobimetallic complexes [Ni(L) 2 (M) 2 R 4 Cl 2 ] were synthesized by using methanolic solution of mononuclear Ni(II) complex and various organometallic dichlorides (where L = o-phenylenediamine (C 6 H 8 N 2), M = Sn(IV), Si(IV), Ti(IV) and Zr(IV) and R = Ph, Me, C 5 H 5 etc.). The synthesized complexes were characterized on the basis of physico-chemical and spectral (FTIR, UV–visible, Mass, 1H NMR) studies. IR spectroscopy confirmed the coordination of –NH 2 group to the metal center. PXRD patterns shown the crystalline nature of all the synthesized complexes. Density Functional Theory study help to correlate the quantum chemical parameters like electronegativity, bond length, bond angles, dipole moment, electrophilicity, hardness, softness and to calculate the energy gap of HOMO and LUMO of the mononuclear metal complex as well as trinuclear heterobimetallic complexes. The frequency computation was done using the hybrid B3LYP functional level of theory. Among the synthesized complexes, mononuclear metal complex adopted square planar geometry while trinuclear heterobimetallic complexes adopted distorted octahedral geometry. The results of PXRD and DFT study exhibited a good correlation. The in-vitro antimicrobial potency of these resulting complexes has been scrutinized and promising results were attained. Moreover, the pesticidal activity of the synthesized complexes was also evaluated against nymph and adult species of Chrotogonus trachypterus by taking into consideration their mortality rate. [ABSTRACT FROM AUTHOR]

[Display omitted] • A heterobimetallic [Mo0;CoIII] complex was synthesized and structurally characterized. • The corresponding monometallic [CoIII] counterpart was also obtained. • Both metals in [Mo0;CoIII] are electronically independent from each other, as shown by cyclic voltammetry. • [Mo0;CoIII] showed very low activity in CO 2 hydrogenation, but no conversion was observed for [CoIII]. A heterobimetallic [Mo0;CoIII] complex and the monometallic [CoIII] counterpart were synthesized and fully characterized. Both metals are electronically independent from each other, as shown by cyclic voltammetry. This is in agreement with previous results, obtained in a separate, previously published study, for the RhIII and IrIII analogues of the mono- and heterobimetallic complexes. The catalytic activity of [Mo0;CoIII] and [CoIII], which was analyzed in this work in homogeneous carbon dioxide hydrogenation to formate was studied. While [Mo0;CoIII] showed very low activity, no conversion was observed for [CoIII]. The low activity is most likely due to instability of the corresponding hydride complex, which could undergo reductive elimination liberating 2-phenylpyridine. [ABSTRACT FROM AUTHOR]

Reactions of Ni(II) and Pd(II) precursors with S -benzyl- N -(ferrocenyl)methylenedithiocarbazate (HFedtc) led to the formation of heterobimetallic complexes of the type [MII(Fedtc) 2 ] (M = Ni and Pd). The characterization of the compounds involved the determination of melting point, FTIR, UV–Vis, 1H NMR, elemental analysis and electrochemical experiments. Furthermore, the crystalline structures of HFedtc and [NiII(Fedtc) 2 ] were determined by single crystal X-ray diffraction. The compounds were evaluated against the intracellular form of Trypanosoma cruzi (Tulahuen Lac-Z strain) and the cytotoxicity assays were assessed using LLC-MK2 cells. The results showed that the coordination of HFedtc to Ni(II) or Pd(II) decreases the in vitro trypanocidal activity while the cytotoxicity against LLC-MK2 cells does not change significantly. [PdII(Fedtc) 2 ] showed the greater potential between the two complexes studied, showing an SI value of 8.9. However, this value is not better than that of the free ligand with an SI of 40, a similar value to that of the standard drug benznidazole (SI = 48). Additionally, molecular docking simulations were performed with Trypanosoma cruzi Old Yellow Enzyme (TcOYE), which predicted that HFedtc binds to the protein, almost parallel to the flavin mononucleotide (FMN) prosthetic group, while the [NiII(Fedtc) 2 ] complex was docked into the enzyme binding site in a significantly different manner. In order to confirm the hypothetical interaction, in vitro experiments of fluorescence quenching and enzymatic activity were performed which indicated that, although HFedtc was not processed by the enzyme, it was able to act as a competitive inhibitor, blocking the hydride transfer from the FMN prosthetic group of the enzyme to the menadione substrate. Image 1 • Heterobimetallic complexes were prepared from a dithiocarbazate derivative (HFedtc). • The in vitro trypanocidal activity and cytotoxicity was assessed. • The selectivity index of HFedtc was similar to that of benznidazole. • The interaction of the compounds with TcOYE was investigated. • HFedtc was able to act as a competitive inhibitor of TcOYE. [ABSTRACT FROM AUTHOR]

• Ferrocene derivatives are active agents against sundry of infectious diseases. • Important conjugates are listed with the corresponding IC 50 values. • Approved drugs and ferrocene derivatives are compared regarding their mode of action. • Ferrocene leads to ROS generation and subsequent lipid, protein and DNA oxidation. • The anti-malarial drug ferroquine is currently in clinical trials. Infectious diseases like malaria, tuberculosis or HIV are among the leading causes of death worldwide according to WHO estimations. Nevertheless, the fight against infectious diseases is aggravated through growing development of resistance towards current drugs and due to their severe adverse effects. The introduction of the lipophilic organometallic moiety ferrocene, a compound with a sandwich-like structure, in an existing bioactive molecule is a promising tool for the development of new more efficient drugs with innovative mechanisms of action. Thus, this review summarizes recent developments in the field of ferrocene conjugation to bioactive molecules like natural products, synthetically derived drugs, peptides as well as heterobimetallic complexes. Hereby, we will provide the reader with a summary of the most potent ferrocene derivatives reported for a plethora of infectious diseases by tabulating and critically assessing the corresponding IC 50 values and the minimal inhibitory concentrations (MIC). Owing to the diverse field of infectious diseases the reported ferrocene derivatives were classified according to their targets into four main groups: antiparasitic (with antimalarial agents as biggest group), antibacterial, antifungal and antiviral agents. [ABSTRACT FROM AUTHOR]

Cu(II)/Mn(II) bimetallic compound with the interesting 3D cation in the structure prepared using two different synthetic routes and characterized by elemental analysis, spectroscopy and single crystal X-ray diffraction. Measurements of magnetic properties revealed a formation of antiferromagnetic Mn(II) chains interconnected by Cu(II) ions with long-range magnetic order below 4.23 K. The synthesis, characterization and crystal structures of the copper complex [Cu(cyclam)Cl 2 ]·H 2 O (1) and bimetallic compound [{Cu(cyclam)MnCl 3 (H 2 O) 2 }Cl] n (2), where cyclam = 1,4,8,11-tetraazacyclotetradecane, are reported. The crystal structure of 1 consists of complexes where Cu(II) is hexacoordinated and has elongated tetragonal-bipyramidal coordination, axial positions are occupied by the oxygen atoms from coordinated water molecules and the basal ones by the nitrogen atoms from the macrocyclic ligand. The reaction of 1 with manganese(II) chloride gives compound 2 with an ionic structure consisting of polymeric cation where Mn(II) and Cu(II) ions are bridged by chlorido ligands. Both central atoms are hexacoordinated and have distorted octahedral coordination environment. In the crystal structure, the formation of two types of chains is observed, one of them contains Cu(II) and Mn(II) ions arranged in alternating manner and perpendicular to them another type of chains consisting of chlorido-bridged Mn(II) atoms is formed. The magnetic properties are characterized by the dominant antiferromagnetic interaction forming Mn(II) chains along c -axis with J Mn /k B = −3.38 K. A long-range magnetic order is formed at 4.23 K in zero magnetic field through the interaction with the Cu(II) subsystem. The analysis of the Arrott plots and critical exponent n describing the field dependence of the entropy change during adiabatic magnetization of the system revealed that the application of a weak magnetic field changes the order of the phase transition from second to the first order. [ABSTRACT FROM AUTHOR]

Lithium amide [(Me 3 TACD)Li] 2 derived from the NNNN macrocycle (Me 3 TACD)H ((Me 3 TACD)H = 1,4,7-trimethyl-1,4,7,10-tetraazacyclododecane) reacted with DIBAL(H) to give the lithium hydridoaluminate [(Me 3 TACD·AlH i Bu 2)Li(THF)] (1 - THF). With HBPin, the lithium hydridoborate [(Me 3 TACD·HBPin)Li] (2) was obtained. Both compounds have been characterized by multinuclear NMR spectroscopy and single crystal X-ray diffraction. The monomeric structure contains a five-coordinate lithium and does not show any interaction between the lithium center and the hydride. Image 1 • Lithium amide [(Me 3 TACD)Li] 2 derived from a NNNN macrocycle gave with DIBAL(H) [(Me 3 TACD·AlH i Bu 2)Li(THF)]. • With HBPin, the hydridoborate [(Me 3 TACD·HBPin)Li] was obtained. • Both heterobimetallic compounds have been characterized by multinuclear NMR spectroscopy and single crystal X-ray diffraction. [ABSTRACT FROM AUTHOR]

• Heterobimetallic [PtM(SAc) 4 (L)] lantern complexes containing divalent Mn, Fe, Co, Ni, and Zn. • Exceptionally long Pt⋯Pt contacts for [PtM(SAc) 4 (pySMe)] with M = Fe, Co, Ni. • Antiferromagnetic coupling observed between [PtM(SAc) 4 (pySMe)] dimers. A new series of heterobimetallic lantern complexes, [PtM(SAc) 4 (pySMe)] (M = Mn (1), Fe (2), Co (3), Ni (4), Zn (5)), as well as additions to the previously reported series, [PtM(SAc) 4 (pyNH 2)] (M = Mn (6), Fe (7)), have been synthesized and thoroughly characterized. Notably, compounds 1 and 6 are the first crystallographically characterized, neutral Pt-Mn containing lantern complexes. Compounds 2 and 7 are the first examples of Pt-Fe containing lantern complexes with a pyridine based axial ligand. These newly synthesized complexes have been characterized by single-crystal X-ray diffraction and UV–vis (1 – 7), 1H and 13C NMR spectroscopies (5), and solution magnetic susceptibility (1 – 4 and 6 – 7) and analyzed in comparison to our previously reported lantern families. Compounds 2 – 4 are isomorphous and contain two crystallographically independent dimers with the same staggered conformations. One dimer has a typical Pt⋯Pt metallophilic interaction ranging from 3.2198(6) to 3.2913(6) Å while the other has a much longer contact ranging from 3.3212(6) to 3.4533(6) Å. These latter contacts suggest metallophilic interactions that are the longest reported to date in any system. Solid state variable-temperature magnetic susceptibility studies suggest antiferromagnetic coupling between the 3 d metal centers in the two lantern complexes of the dimeric forms of 2 , 3 , and 4. [ABSTRACT FROM AUTHOR]

The synthesis of six chiral titanium-containing phosphinoamide ligands is discussed. These ligands assemble chiral heterobimetallic Pd–Ti complexes, enable enantioselective intramolecular allylic aminations with hindered amine nucleophiles and achieve selectivity up to 53% ee. Mechanistic studies demonstrate the reversibility of the enantio-determining C–N bond forming step, which leads to a gradual increase in the % ee of the reaction over time. These results represent a rare example of enantioselective heterobimetallic catalysis and suggest that these new ligands could find broad application in enantioselective transition metal catalysis. Image 1 [ABSTRACT FROM AUTHOR]

A new trinuclear organometallic palladium(II) complex was synthesized and compared with the trinuclear heterobimetallic platinum(II) analogue. The trinuclear platinum(II) complex shows higher potential anticancer activities than palladium(II) one. Addition of H 2 R 2 DTO (R = { S }-1-phenylethyl and DTO = dithiooxamide) to the bis(benzonitrile)palladium(II) chloride complex in chloroform afforded the mononuclear Pd(DTO) 2 ·2HCl complex. The complex treated with NaHCO 3 for removing of HCl and then reacted with [Pd(ƞ 3-allyl)(µ -Cl)] 2 for preparation of a new trimetallic organopalladium(II) complex. The molecular structure of the trimetallic complex was determined by X-ray diffraction indicating a planar geometry around each palladium center. Also, variable temperature spectroscopy for this complex was performed in CDCl 3 in the range 298–390 K, and simulations of the dynamic spectra were performed using the gNMR program. A comparison between the target-based activity of the Pd(II) complex and its trinuclear heterobimetallic platinum(II) analogue as potential anticancer agents was also conducted. All the biological tests showed that both Pd(II) and Pt(II) complexes can fairly inhibit cathepsin B (Cat-B) and cathepsin L (Cat-L) as well as two out of three activities of 20S proteasome. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Heterometallic Fe-Mn complex synthesized and characterized. • The Fe-Mn complex reacts faster with oxygen higher than Fe-Fe and Mn-Mn complexes. • The CV of the Fe-Mn complex shows richer chemistry than Fe-Fe and Mn-Mn complexes. • Fe can replace Mn in the Mn-Mn complex to give Fe-Mn complex. Abstract Heterobimetallic cofactors containing one manganese and one iron ion have recently been found within the di-metal carboxylate protein family. Herein we report the synthesis and characterization of three binuclear metal complexes with Fe-Fe, Mn-Mn, and Fe-Mn metal composition. All three complexes use the same ligand framework, the BPMP ligand (HBPMP = 2,6-bis[(bis (-2-pyridylmethyl)amine) methyl]-4-methylphenol)) with two additional acetate ligands bridging the two metals. In terms of stability towards metal exchange, the Fe-Mn is more stable than the Mn-Mn complex but less stable than the Fe-Fe complex. Cyclic voltammetry shows that the Fe-Mn complex behaves markedly different than the homobimetallic complexes. The Fe-Mn complex also shows higher reactivity with O 2 than both the Fe-Fe and the Mn-Mn counterparts. [ABSTRACT FROM AUTHOR]

Abstract A new series of asymmetrical heterobimetallic azines [(η5-C 5 H 5)Fe{(η5-C 5 H 4) C(R) = N N C(R1)-(η5-C 5 H 4)Re(CO) 3 }] (1–3) and symmetrical homobimetallic cyrhetrenyl azines [{(η5-C 5 H 4) C(R) = N}Re(CO) 3 ] 2 (4 , 5) have been synthesized and were spectroscopically characterized by FT-IR, NMR, EI-MS and cyclic voltammetry. The molecular structures of 1 and 4 were determined using single-crystal X-ray diffraction technique. Based on the oxidation potential of the ferrocenyl units and the high degree of planarity of the [(C 5 H 4) C(H) = N N C(H)-(C 5 H 4)] system in complex 1 , we inferred electronic communication between the electron-withdrawing cyrhetrenyl groups through the π-conjugated azine bridge. The compounds display an (E,E)-configuration about the >C N- bond, an s-trans conformation for the N N bond and an anti -conformation for the two organometallic fragments. Graphical abstract The synthesis of new organometallic symmetrical homo- and unsymmetrical hetero-bimetallic azines containing a ferrocenyl and cyrhetrenyl moieties are described. Electronic communication between the organometallic fragments was assigned on the bases of E 1/2 and coplanarity of the [(C 5 H 4) C(H) = N N C(H)-(C 5 H 4)] system. Image 1 Highlights • Homo- and hetero-bimetallic azines containing cyrhetrene and ferrocene were synthesized and characterized. • E 1/2 and coplanarity of the [(C5H4)-C(H)=N-N=C(H)-(C5H4)] system indicate electronic communication. • Compounds exhibit E,E isomerism, s-trans conformation of the N-N bond and anti -conformation. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • New coordination polymers through the complex as ligand strategy. • Crystal structures of heterobimetallic assemblies. • One-dimensional oxalato-bridged bimetallic compounds. • The metalloligand strategy envisaging tailor-made heterobimetallic species. Abstract Four new coordination polymers based on the use of the [Cr(pyim)(C 2 O 4) 2 ]− species as a metalloligand, namely [LiCr(pyim)(C 2 O 4) 2 (MeOH)] n (1), {[CaCr 2 (pyim) 2 (C 2 O 4) 4 ]·2MeOH} n (2), {[SrCr 2 (pyim) 2 (C 2 O 4) 4 (H 2 O)]·0.45MeOH·4.55H 2 O} n (3) and {[CdCr 2 (pyim) 2 (C 2 O 4) 4 ]·MeOH} n (4) [pyim = 2-(2′-pyridyl)imidazole] have been synthesized and characterized by elemental analyses, IR spectra and X-ray diffraction on single crystals. Complex 1 is a neutral heterobimetallic chain where the tris(chelated) chromium(III) unit acts as a bis-bidentate ligand towards {Li(MeOH)}+ fragments through its two oxalate ligands, each lithium ion being five-coordinate in a intermediate surrounding between square pyramidal and trigonal bipyramidal. The structure of 2 consists of neutral oxalato-bridged chromium(III)-calcium(II) double chains of single chirality [all the tris(chelated) chromium centres have the same chirality either Λ or λ] and methanol molecules of crystallization. Each calcium ion in 2 exhibits a square antiprism environment which is built by four bidentate oxalate ligands from four [Cr(pyim)(C 2 O 4) 2 ]− units. Neutral oxalato-bridged chromium(III)-strontium(II) double chains also occur in 3 with methanol and water molecules of crystallization, each alkaline-earth cation being nine-coordinate in a monocapped square antiprism environment which is defined by a water molecule and eight oxalate-oxygens from four [Cr(pyim)(C 2 O 4) 2 ]− units. The CrIII 2 MII 2 loops [M = Ca (2) and Sr (3)] within each double chain are planar. The structure of 4 is also made of neutral oxalato-bridged chromium(III)-cadmium(II) double chains but in contrast to 2 and 3 , the chirality of the tris(chelated) chromium unit in 4 is alternated in each loop and the adjacent CrIII 2 CdII 2 loops are not planar but form a dihedral angle of 84.8°. The potential use of the [Cr(pyim)(C 2 O 4) 2 ]− entity as a metalloligand in designing heterobimetallic compounds is analyzed and discussed. [ABSTRACT FROM AUTHOR]

Graphical abstract Complex [ZnFe(L) 3 Cl](NO 3)·3(MeOH)·3(DMF) can catalyze the ring opening of epoxides with aromatic amines to produce β-amino alcohols at room temperature. Abstract Four heterobimetallic coordination polymers [Cd[Al(L) 3 ] 2 (NO 3) 2 (1), Zn[Al(L) 3 ] 2 (NO 3) 2 (2), Zn[Fe(L) 3 ] 2 (NO 3) 2 (3), and [ZnFe(L) 3 Cl](NO 3)·3(MeOH)·3(DMF) (4) have been synthesized. The structural analyses of coordination polymers 1 – 4 showed that they were trigonal space group, among which, coordination polymer 4 was P 3 chiral space group. The circular dichroism spectra also confirmed that coordination polymer 4 had chirality. Zn(II) ion in coordination polymer 4 was tetracoordinated, unsaturated, can act as Lewis acid catalyst. Therefore, coordination polymer 4 can catalyze the ring opening of epoxides with aromatic amines to produce β-amino alcohols at room temperature. The catalytic reaction was regioselective, easy to operate, and had good catalyst recovery and repeatability. [ABSTRACT FROM AUTHOR]

Predictive models for bond strengths between aluminum and various transition metals were derived by combining DFT calculations with multivariate linear regression analysis. [Display omitted] • A series of heterobimetallic Al–M complexes (M = Cr, Mn, Co, Mo, Ru, W) was screened computationally. • Predictive models for Al–M bond strength were derived by combining DFT and multivariate linear regression analysis. • Al–M and M−H bond strengths share common contributors, but steric and orbital overlap parameters provide additional influence on Al–M bonds. • Extrapolation enables predictions of Al–M bond strengths without requiring DFT. It was previously shown that the complex, LAl(Me)Fp [where L is a β-diketiminate and Fp = FeCp(CO) 2 ] undergoes Al-Fe homolysis at ambient conditions, revealing a pair of metalloradical intermediates capable of cooperative small molecule activation. Towards expanding this platform to other Al–M derivatives, here we conducted an extensive computational screening of potential LAl(Me)M catalysts (where M is a series of common metal carbonyls) using DFT calculations combined with multivariate linear regression (MLR) analysis. Predictive models were established that anticipate the influences of different metals on Al–M bond dissociation free energies (BDFEs), utilizing electronic and steric parameters obtained from existing literature and from buried volume calculations (% V bur), including a convenient model that can be applied without aid of further DFT calculations. Our investigations unveiled a partial correlation between Al–M BDFEs and M−H BDFEs, in that both depend on p K a and E ° values of M. However, Al–M BDFEs demonstrate significant influences from both steric crowding and Al–M orbital overlap, neither of which contribute to M−H BDFE. By employing MLR to derive predictive models, extrapolation to other hypothetical complexes beyond the training set presented in this study is facilitated. Thus, our research will inform and enable the future design of sustainable catalytic processes involving heterobimetallic Al–M complexes with earth-abundant metals. [ABSTRACT FROM AUTHOR]

Abstract Three one-dimensional (1D) cyanide-bridged heterobimetallic chains {[FeIII(Tp)(CN) 3 ] 2 CoII(mep) 2 }·2CH 3 OH (1 ; Tp = hydrotris(pyrazolyl)borate, mep = 4‑[(1 E)‑2‑(4‑Methylphenyl)ethenyl]pyridine), {[FeIII(Tp)(CN) 3 ] 2 CoII(eep) 2 }·2CH 3 OH (2 ; eep = 4‑[(1 E)‑2‑(4‑Ethylphenyl)ethenyl]pyridine) and {[FeIII(Tp)(CN) 3 ] 4 CoII 2 (nep) 4 }·3H 2 O·CH 3 OH (3 ; nep = 4‑[(1 E)‑2‑(2‑Naphthalenyl)ethenyl]pyridine) have been synthesized via self-assembly of the same [FeIII(Tp)(CN) 3 ]− unit and CoII ion in the presence of different N -substituted pyridine ligands. Magnetic measurements reveal that complex 1 exhibits ferromagnetic interactions and a long-range magnetic ordering below 3.5 K. Complex 2 shows antiferromagnetic long-range ordering below 3.3 K, while complex 3 shows a typical ferrimagnetic coupling at low temperatures. These results highlight the significant influence of the coligands on their magnetic properties. Graphical abstract Three one-dimensional cyanide-bridged {FeIII 2 CoII} n chains with different N -substituted pyridine ligands were synthesized and characterized. Magnetic measurements reveal that complex 1 exhibits ferromagnetic interactions and a long-range magnetic ordering. Complex 2 shows antiferromagnetic long-range ordering, while complex 3 shows a typical ferrimagnetic coupling. The alteration of the coligands greatly influences the magnetic coupling interactions and finally results in different magnetic properties. Unlabelled Image Highlights • Three one-dimensional cyanide-bridged {FeIII 2 CoII} n chains were synthesized. • Magnetic measurements indicated that three compounds displayed completely different behavior. • The alteration of the coligands results in different magnetic properties. [ABSTRACT FROM AUTHOR]

The superficial chemical environment of the catalyst supports played an important role in heterometallic catalysts preparation. The functions of hydroxy groups on the surface of SiO 2 nanosphere was investigated in catalyst preparing and cellulosic biomass conversion to ethylene glycol (EG). The results demonstrated that 15%Ni-20%W/SiO 2 -OH catalyst was favorable for EG production, with the highest yield of 63.1 and 42.1% from microcrystalline cellulose and hardwood pulp, respectively. The characterization and activity tests suggested that the existence of hydroxy groups could promote the formation of more Ni-W alloys (e.g. NiW, Ni 4 W) under the same preparing condition, which supplemented and enhanced the incorporation of intrinsic nickel and tungsten catalytic activity, especially for enhancement of retro-aldol condensation reaction. Moreover, the metallic Ni 0 was generated in higher amount when supported on hydroxy-rich SiO 2 , boosting hydrogenation of the unsaturated intermediates. Finally, the reusability investigation of the catalyst implied that embedded Ni and W in alloys could inhibit leaching of metals in pressurized hot water. [ABSTRACT FROM AUTHOR]

Searching for prospective agents against infectious diseases, four new ferrocenyl derivatives, [M(L)(dppf)4](PF 6 ), with M = Pd(II) or Pt(II), dppf = 1,1′-bis(dipheny1phosphino) ferrocene and HL = tropolone (HTrop) or hinokitiol (HHino), were synthesized and characterized. Complexes and ligands were evaluated against the bloodstream form of T. brucei , L. infantum amastigotes, M. tuberculosis (MTB) sensitive strain and MTB clinical isolates. Complexes showed a significant increase of the anti- T. brucei activity with respect to the free ligands (>28- and >46-fold for Trop and 6- and 22-fold for Hino coordinated to Pt-dppf and Pd-dppf, respectively), yielding IC 50 values < 5 μM. The complexes proved to be more potent than the antitrypanosomal drug Nifurtimox. The new ferrocenyl derivatives were more selective towards the parasite than the free ligands. The Pt compounds were less toxic on J774 murine macrophages (mammalian cell model), than the Pd ones, showing selectivity index values (SI = IC 50 murine macrophage/IC 50 T. brucei ) up to 23. Generation of the {M-dppf} compounds lead to a slightly positive impact on the anti-leishmanial potency. Although the ferrocenyl derivatives were more active on sensitive MTB than the free ligands (MIC 90  = 9.88–14.73 μM), they showed low selectivity towards the pathogen. Related to the mechanism of action, the antiparasitic effect cannot be ascribed to an interference of the compounds with the thiol-redox homeostasis of the pathogen. Fluorescence measurements pointed at DNA as a probable target of the new compounds. [Pt(Trop)(dppf)](PF 6 ) and [Pt(Hino)(dppf)](PF 6 ) could be considered prospective anti- T. brucei agents that deserve further research. [ABSTRACT FROM AUTHOR]

A classical-quantum chain composed of regularly alternating Ising and Heisenberg spins is rigorously solved by considering two distinct local anisotropy axes of the Ising spins. The ground-state phase diagram and magnetization curves are examined depending on a spatial orientation of the applied magnetic field. The phase diagram totally consists of four distinct phases and a few macroscopically degenerate points, where an outstanding coexistence of perfect order and complete disorder occurs within the so-called ‘half-fire, half-ice’ state. The zero-temperature magnetization curves generally exhibit a smooth dependence on a magnetic field owing to a canting angle between two coplanar anisotropy axes of the Ising spins, which enforces a misalignment of the magnetization vector from a direction of the applied magnetic field. It is evidenced that the investigated spin-chain model reproduces magnetic features of the heterobimetallic coordination compound Dy(NO) 3 (DMSO) 2 Cu(opba)(DMSO) 2 (DMSO = dimethylsulfoxide, opba = orthophenylenebisoxamato). The high-field magnetization data reported for the powder sample of this polymeric coordination compound generally display a substantial smoothing on account of a powder averaging. [ABSTRACT FROM AUTHOR]

The encapsulation of Pt and Au-based anticancer agents within a protein cage is a promising way to enhance the selectivity of these potential drugs. Here a cytotoxic organometallic compound containing platinum(II) and gold(I) has been encapsulated within a ferritin nanocage (AFt). Inductively plasma coupled mass spectrometry data, collected to evaluate the amount of Pt and Au within the cage, indicate disruption of the starting heterobimetallic complex upon encapsulation within the nanocage. The drug-loaded protein (Pt(II)/Au(I)-AFt) has been characterized by UV–Vis spectroscopy, circular dichroism and X-ray diffraction analysis. Data indicate that the protein maintains its fold upon encapsulation of the metallodrug and that Au(I) and Pt(II)-containing fragments are encapsulated within the AFt cage, with Au(I) ion that binds the side chain of Cys126 and Pt(II) in the bulk, respectively. The in vitro cytotoxicity of Pt(II)Au(I)-AFt, as well as that of the free heterobimetallic complex, has been comparatively evaluated on human cervix and breast cancer cells and against cardiomyoblasts and keratinocytes non-tumorigenic cells. Our data demonstrate that it is possible to obtain a protein nanocarrier containing both Pt and Au atoms starting from a bimetallic compound, opening the way for the design and development of new potential drugs based on protein nanocarriers. [ABSTRACT FROM AUTHOR]

Five new heterometallic complexes with a {Ln[ RuNO ( µ - NO 2 ) 4 ( µ 3 - OH )] 2 Ln} (Ln = Gd, Tb, Dy, Ho, Lu) core were prepared by the reaction of Na 2 [RuNO(NO 2 ) 4 OH] with lanthanide nitrates. Investigation of magnetic properties showed that magnetic interactions between lanthanide ions become apparent at temperatures lower than 40–50 K, while at temperatures higher than 100 K the dependencies of magnetic susceptibility of the complexes are well explained by the presence of two non-interacting paramagnetic centres. Frequency dependencies of magnetic susceptibility for the dysprosium complex in the temperature range 10–30 K revealed single molecule magnet (SMM) properties with a thermally activated slow magnetic relaxation process. The anisotropy barrier is 89.4 cm −1 (112 K) and τ 0  = 7.6 × 10 −7  s. Irradiation of the Dy 2 Ru 2 complex with blue light (443 nm) at 80 K resulted in the formation of nitrosyl linkage isomers of the RuNO fragment; the T d of reverse isomerisation is 195 K. [ABSTRACT FROM AUTHOR]

From an aqueous-ethanolic solution of CuCl 2 , 5,5′- dmbpy (5,5′- dmbpy  = 5,5′-dimethyl-2,2′-bipyridine) and K 2 [Ni(CN) 4 ], a novel Cu/Ni heterobimetallic complex [Ni(5,5′- dmbpy ) 3 ] 2 [NiCu 2 (CN) 8 ]·6H 2 O was isolated and characterized. Its ionic crystal structure contains the unprecedented Cu(I)/Ni(II,D 4h ) complex anion [Cu 2 Ni(CN) 8 ] 4− , along with the rarely structurally characterized [Ni(5,5′- dmbpy ) 3 ] 2+ complex cation and water solvate molecules. The anions and water molecules are linked by hydrogen bonds, yielding a 1D supramolecular structure. Magnetic measurements performed down to 1.8 K revealed a Curie behavior between 15 and 300 K, while a small zero field splitting effect can be seen below 15 K. [ABSTRACT FROM AUTHOR]

A multidentate O,N,O P ligand 4 designed for early–late heterobimetallic (ELHB) complexes was synthesized. The ligand 4  has an O,N,O-tridentate ligand moiety and a triarylphosphine group. The O,N,O-moiety based on lutidine scaffold selectively coordinated to early transition metals such as titanium and niobium in the reaction with the corresponding metal alkoxides to form mononuclear complexes. Coordination of the triarylphosphine moiety to the niobium atom was negligible in the Nb-ONO P complex according to 31 P NMR spectroscopy, whereas a part of the phosphorus atom coordinated to the titanium atom in the Ti-ONO P complex. Addition of [PdCl(π-allyl)] 2 or [RhCl(cod)] 2 to the Nb-ONO P complex gave rise to the formation of ELHB complexes. Thus, the one-pot preparation of ELHB complexes was achieved by simple procedure. [ABSTRACT FROM AUTHOR]

Heterobimetallic complexes of the composition [CuNi(bpy) 2 (μ-OAc) (μ-OH) (μ-OH 2 )](BF 4 ) 2 (1) and [CuNi(bz) 3 (bpy) 2 ]ClO 4 (2) were synthesized in moderate yield through solid state reaction and have been characterized by elemental analyses, molar conductance, mass spectra, magnetic moment, EPR, UV–Vis, IR spectroscopies and cyclic voltammetry. The ground state in complex (1) is doublet while that in complex (2), the ground state is a mixture of doublet and quartet, respectively. The structure of the complexes has been established by X-ray crystallography. The electron transfer reactions of the complexes have been investigated by cyclic voltammetry. [ABSTRACT FROM AUTHOR]

The first SCN-bridged Mg–Ag coordination polymer, namely [Mg(DMF) 4 Ag 2 (SCN) 4 ] n ( 1 ) (DMF = N,N-dimethylformamide) has been synthesized and structurally characterized by FT-IR spectroscopy, elemental analysis and single crystal X-ray diffractions. X-ray structural analysis reveals that 1 displays a two-dimensional (2-D) framework, which contains Mg metallic atoms, Ag 2 dimeric units, and SCN − bridges with two kinds of connected manners. This Mg–Ag coordination polymer exhibits strong luminescence property and can act as highly sensitive sensor for 2,4,6-Trinitrophenol in both DMF and aqueous media. Moreover, the mechanism of 1 for highly sensitive detection of TNP had been preliminarily studied. [ABSTRACT FROM AUTHOR]

A new series of heterobimetallic complexes [Cu(PPh 3 )(NC 5 H 4 HC NC 6 H 4 C CC 6 H 4 C CRu (dppe) 2 Cl)X] ( 1a-5a ) have been prepared by the reaction of trans- (NC 5 H 4 HC NC 6 H 4 C CC 6 H 4 C C Ru(dppe) 2 Cl) with copper salts in presence of triphenylphosphine (where X = Cl, Br, I, N 3 , NCS). Our synthetic attempts and successes are discussed in combination with spectroscopic and electronic characterization of the compounds. Comparison between halides and pseudohalides were studied by thermal and electrochemical analysis where, thermally robust complexes demonstrate quasireversible redox behaviour analogous to Cu I/II /Ru II/III couple. Room temperature luminescence with varying electron donating and quenching abilities of halides and pseudohalides in blue-green region were observed. Concentration and solvent dependant emission displays positive solvatochromism at ambient temperature. [ABSTRACT FROM AUTHOR]

• The UV-induced C-H activation mechanism is a good alternative catalytic cycle. • The re-coordination of CO to the Fe occurs before the releasing of H 2. • Benzene with strong electron-withdrawing group is favorable to the para -product. The heterobimetallic complex [(NHC)Cu-FeCp(CO) 2 ] ([LCu-Fp]) is an efficient and sustainable catalyst for C-H borylation under UV light irradiation, whereas the catalytic mechanism is still debating. One opinion is the thermal induced mechanism, in which Cu-Fe bond in [LCu-Fp] firstly dissociated by B-H activation, and then induced the decarbonylation of FpBpin by UV irradiation. The other is the UV-induced mechanism, the decarbonylation of [LCu-Fp] occurred before the Cu-Fe broken. In this work, detailed mechanism of UV-induced has been investigated by DFT calculations and compared with the thermal induced mechanism. Our calculated results show that both of them can occur under UV light irradiation at room temperature. The UV-induced mechanism contains four steps: CO dissociation, Cu-Fe bond breakage by B-H activation, C-H borylation, and H-H reductive elimination. In the last step, it is the re-coordination of CO to the Fe occurs before the releasing of H 2. The strong election-withdrawing substituent of benzene would increase the yield of para -product, whereas the election-donating substituent has little influence on the regioselectivity. Our calculation determines the detail mechanism of the title reaction and provides reasonable explanation for the regioselectivity of C-H borylation of substituted benzene, which would help for the widely usages of the heterobimetallic catalysts. The detailed mechanism of UV-induced decarbonylation of [LCu-Fp] in B-H activation process in C-H Borylation was investigated by DFT calculations and compared with the thermal-induced B-H activation process. Both of the two cases can occur under UV light irradiation at room temperature. The strong election-withdrawing substituent of benzene would increase the yield of para -product, whereas the election-donating substituent has little influence on the regioselectivity. [Display omitted] [ABSTRACT FROM AUTHOR]

This review deals with the coordination of alkynes as reactive unsaturated substrates on heterobimetallic transition metal complexes L n M–M′L n in which two transition metal centers interact through a metal–metal bond spanned by a diphosphane ligand such as bis(diphenylphoshino)methane or a bridging phosphido group of the type μ-PR 2 . Presented are few examples featuring simple π-coordination of the alkyne on M or M′, but the majority of examples involve bimetallic activation associated with synergetic effects of the two adjacent metal centers giving rise to dimetallatetrahedranes, dimetallacyclobutenes, dimetallated olefins, μ-vinylidenes and acetylides species. Covered are also heterobimetallic systems, in which carbon–carbon or carbon-phosphorus couplings have occurred between two alkyne ligands or with carbonyl groups and P-donor ligands present in the coordination sphere of the heterodinuclear scaffold. Furthermore, hydrometallation reactions leading to vinyl-species through insertion of R-C C-H or R-C C-R into a terminal or bridging M–H bond are presented. Included in this review are also selected examples of reactivity studies and transformation of the initially formed heterobimetallic alkyne species, such as addition of electrophiles (H + , R + ), generating heterometallic alkenyl and µ-η 1 :η 2 -allenyl salts. [ABSTRACT FROM AUTHOR]

Heteromultimetallic hydride complexes consisting of both rare-earth and d-transition metals are expected to exhibit unique reactivity because they have potential to show the synergistic effect of the substantially different types of metal centers. Here we report the reactions of rare-earth/ruthenium heterobimetallic dihydride complexes [Cp*Lu(THF)( μ -H) 2 ( μ - η 1 : η 1 -CHRP(CH 2 R) 2 )RuCp*] and [(C 5 Me 4 SiMe 3 )Y(DME)( μ -H) 2 ( μ - η 1 : η 1 -C 6 H 4 PPh 2 )RuCp*] (R = H, Me; Cp* = C 5 Me 5 ) with carbon monoxide. C–O bond cleavage and C–C bond formation, as well as P–C bond cleavage of the phosphine ligand occurred through the cooperation of two different metal centers. Dependence of the reaction pattern on the substituents of the phosphine ligands was also observed. [ABSTRACT FROM AUTHOR]

A new hydroxymethyl-pendant salan ( 3 ) containing a chiral backbone and an extra O 4 cavity has been prepared through a facile one-pot procedure. The ligand has been characterized by ESI-MS, elemental analysis and 2D NMR techniques. To continue our previous work on the catalytically asymmetric F-C reactions using multimetallic complexes involving salan-type ligands, we investigated the applicability of 3 for both asymmetric Henry and F-C reactions, in comparison with previously reported results using salans 1 and 2 . It was revealed that although 3 was not a suitable ligand for homometallic copper-catalyzed Henry reaction, it was effective for the hetereobimetallic Cu/Zn-catalyzed asymmetric F-C reaction, affording desired alkylated product with good yield and moderate enantiomeric excess (ee), after screening of various catalyst combinations. [ABSTRACT FROM AUTHOR]

Two new heterobimetallic ruthenium (II) complexes with general formula [Ru(N-S)(bipy)(dppf)]PF 6 (bipy = 2,2’-bipyridine, N-S = 2-mercaptothiazolinate – mctz − ( 1 ) and 2-mercaptobenzothiazolinate – mcbtz − ( 2 ); dppf = 1,1’-bis{diphenylphosphino}ferrocene) were synthesized from the reaction of cis- [RuCl 2 (bipy)(dppf)] and 2-mercaptothiazoline (Hmctz) or 2-mercaptobenzothiazoline (Hmcbtz), in the presence of triethylamine (NEt 3 ) and KPF 6 in MeOH, under reflux. The complexes were characterized by NMR ( 31 P{ 1 H}, 1 H and 13 C), vibrational spectroscopy (FTIR), cyclic voltammetry, molar conductivity, UV-Vis and elemental analysis (%C, %H, %N, and %S). Furthermore, the molecular structure of complexes 1 and 2 were solved by X-ray diffraction studies. UV-Vis spectroelectrochemistry studies were carried out for complex 2 in order to unravel the processes observed in the cyclic voltammetry. DFT analysis of complexes 1 , 2 and the precursor complex cis- [RuCl 2 (bipy)(dppf)] revealed the composition of the frontiers orbitals, supporting the assignment of the electrochemical behavior of the complexes. The antibacterial potential of the new complexes and the free ligands (dppf, mctz − and mcbtz − ) were assessed in vitro against Staphylococcus aureus, Staphylococcus epidermidis, E. coli and P. aeruginosa. The 1,1-diphenyl-2-picrilhidrazyl (DPPH) radical scavenging ability (antioxidant activity) was also evaluated. [ABSTRACT FROM AUTHOR]

Present work demonstrates the synthesis of a novel heterobimetallic complex [Mg 2 TiO(TFA) 6 (THF) 2 (H 2 O)] ( 1 ) (where TFA = trifluoroacetato and THF = tetrahydrofuran), formed from the chemical interaction of magnesium (II) acetate tetrahydrate with titanium (IV) isopropoxide and trifluoroacetic acid in THF solution. Complex ( 1 ) adequately characterized through attenuated total reflection infrared spectroscopy, single-crystal X-ray diffraction and thermogravimetric analysis was implemented as single source molecular precursor in the aerosol assisted chemical vapor deposition. The deposition of magnesium orthotitanate (Mg 2 TiO 4 ) ceramic films on fluorine doped tin oxide coated conducting glass substrate was observed at various temperatures of 500, 550 and 600 °C. Film characterization techniques including; X-ray powder diffraction, scanning electron microscopy, energy dispersive X-ray and X-ray photoelectron spectroscopy divulge the fabrication of phase pure spherical shaped Mg 2 TiO 4 architectures with precise stoichiometry and high purity. [ABSTRACT FROM AUTHOR]

Two aryloxide-substituted N-heterocyclic carbene (NHC) proligands 3-[(2-hydroxynaphthalenyl) methyl]-1-mesityl-3,4,5,6- tetrahydropyrimidinium chloride ( H 2 L1 ) and 3-(2-hydroxybenzyl)-1-mesityl-3,4,5,6-tetrahydropyrimidinium chloride ( H 2 L2 ) were designed and easily synthesized via three synthetic processes in high yield. Four heterobimetallic potassium-NHC rare earth complexes L1 KLnN″ 3 and L2 KLnN″ 3 ( L1 , Ln = Y ( 1a ), Nd ( 1b ); L2 , Ln = Y ( 2a ), Nd ( 2b ), N″ = N(SiMe 3 ) 2 ) were obtained by in-situ reaction of N-heterocyclic carbene proligands H 2 L1 and H 2 L2 with Ln[N(SiMe 3 ) 2 ] 3 and KN(SiMe 3 ) 2 in toluene. The K-NHC rare earth complexes were characterized by single-crystal X-ray crystallography and Y complexes were characterized by 1 H and 13 C NMR spectroscopy. DFT calculations were employed to further investigate charge distributions and interactions within these compounds. [ABSTRACT FROM AUTHOR]

Experimental and DFT study on the ring flipping phenomenon from the two fused puckered five–membered rings in complex [PNP(Me)(CH 3 CN)Ir-ReO 3 ][PF 6 ] ( 2 ) and its derivative [PNP(Me)(CN t Bu)Ir-ReO 3 ][PF 6 ] ( 3 ) is reported here. Dynamic NMR studies from 31 P{ 1 H}NMR on ring flipping revealed that complexes 2 and 3 possess ΔG ‡ value of 11.2 ± 0.3 and 9.2 ± 0.3 kcal/mol at 298 K respectively. Density Functional Theory (DFT) calculations concurred with the Potential Energy (PE) values of 12.36 and 8.09 kcal/mol respectively for the same phenomena. Also, DFT studies revealed that ring flipping and structural isomerism between 2 and its isomer [PNP(H)Ir-μ(CH 2 )-μ(O)-Re(O) 2 ][PF 6 ] ( 1 ) possess distinct transition states and can occur concurrently as observed experimentally. [ABSTRACT FROM AUTHOR]

A ratiometric fluorescent sensor towards carbonate ions (CO 3 2− ) based on a heterobimetallic metal-organic frameworks (Eu/Pt-MOFs) have been synthesized under a facile hydrothermal condition. And then the as-synthesized MOFs are characterized by PXRD, FT-IR, TG, fluorescence spectroscopy and its lifetime (τ). The Eu/Pt-MOFs not only shows dual-emission with a broad band centered at about 560 nm and a characteristic emission of Eu 3+ but also have good stability in the aqueous solution, which was further used as a novel fluorescence probe for detecting CO 3 2− . With CO 3 2− addition, the luminescence of Eu 3+ is enhanced while the broad band is suppressed significantly. The relative intensity ratio of I Eu(614) /I Ligand linearly with increasing concentration of CO 3 2− with 0.021 μM detection limit, which much lower than the content of carbonate in accordance with the nutritional and hygienic standards and guidelines for quality certification in children's preferable food. Besides, the robust Eu/Pt-MOFs sustain good stability in aqueous environment, excellent selectivity, fast detection time and applying to different water samples. This work makes the direct, rapid and reliable detection of carbonate ions for practical application possible. [ABSTRACT FROM AUTHOR]

A new series of azobenzene based heterobinuclear coordination-organometallic hybrid complexes of the type [Zn( phen )(R C 6 H 4 HC N(O)C 6 H 3 N NC 6 H 4 C CRu(dppe) 2 Cl)]X ( 1a-6a ) and [Zn( bipy )(R C 6 H 4 HC N(O)C 6 H 3 N NC 6 H 4 C CRu(dppe) 2 Cl)]X ( 1b-6b ) have been prepared and characterized (where R= C CC 6 H 4 OCH 3 , C CC 6 H 4 NO 2 ; X ClO 4 , BF 4 , PF 6 ; phen = 1,10-phenanth-roline, bipy = 2,2′-bipyridine). TGA was carried out to study the thermal behaviour of the complexes. X-ray powder diffraction and SEM studies of the representative complexes 2a and 5b are used to clarify the crystal structure and morphology of the complexes. Cyclic voltammetry study indicate a quasireversible redox behaviour corresponding to Ru(II)/Ru(III) couple susceptible to variation of electron donating/accepting properties of substituent group in the complexes. Room temperature luminescence is observed for all complexes corresponding to π→π*ILCT transition indicating that the emission wavelength is finely tuned by increasing π-conjugation and variation of substituent groups with different electronic effects in the complexes. The second harmonic generation (SHG) efficiency of the complexes was measured by Kurtz-powder technique indicating that all complexes display the second harmonic generation (SHG) property. [ABSTRACT FROM AUTHOR]

The phosphinimine, trimethylsilyl-substituted BIPM ligand [BIPM = bis(iminophosphorano)methanide] has been used to stabilise CH(Ph 2 PNSiMe 3 ) 2 MgFe(η 5 -C 5 H 5 )(CO) 2 ( 1 ), which is a structurally authenticated complex exhibiting a direct, unsupported bond between an alkaline earth metal and a transition metal. The FTIR-measured carbonyl stretching frequencies for this complex suggest that there is a polarisation of charge from the transition metal fragment to the magnesium centre. The presence of a polar metal-metal bond in 1 is confirmed by DFT calculations, which suggest that the Mg–Fe bond is predominantly ionic in nature. [ABSTRACT FROM AUTHOR]

Reactions of [Pt(SeC 5 H 4 N) 2 (P∩P)] with M(OAc) 2 .2H 2 O/MX 2 (P∩P = dppm, dppp; M = Zn, Cd, Hg, Cu; X = Cl) resulted various products depend upon the nature of the phosphine. In case of dppm, reaction between [Pt(SeC 5 H 4 N) 2 (dppm)] and M(OAc) 2 .2H 2 O/MX 2 (M = Zn, Cd, Hg) afforded an exchange product of composition [PtCl 2 (dppm)]. Similarly, the reaction with ‘dppp’ analog yielded an adduct [{Pt(SeC 5 H 4 N) 2 (dppp)}MX 2 ] (M = Cd, Hg, Cu; X = Cl, OAc). Whereas, reaction with Zn(OAc) 2 , on extraction with dichloromethane resulted the product with the loss of one selenium atom of composition [{Pt(C 5 H 4 N)(SeC 5 H 4 N)(dppp)}ZnCl 2 ]. These complexes were characterized by elemental analyses and NMR ( 1 H, 31 P, 77 Se, 195 Pt) spectroscopy. The molecular structure of [{Pt(C 5 H 4 N)(SeC 5 H 4 N)(dppp)}ZnCl 2 ] was established by single crystal X-ray diffraction analyses. [ABSTRACT FROM AUTHOR]

A tetranuclear cluster {[(Tp)Fe(CN) 3 ]Co(pp)H 2 O} 2 ·[(Tp)Fe(CN) 3 ] 2 ⋅ 6H 2 O ( 1 ; Tp = hydrotris(pyrazoly)borate, pp = 2,6-bis(N-pyrazolyl)pyridine) and a hexanuclear cluster {[(pzTp)Fe(CN) 3 ] 2 Co(pp)} 2 ·2H 2 O ( 2 ; pzTp = tetrakis(pyrazoly)borate) have been synthesized via rational assembly of the same (ppCo II ) 2 + unit and different tricyanometalate building blocks with varying proportions of sterically hindered groups. Magnetic measurements reveal that 1 exhibits the dominant antiferromagnetic interactions between Fe(III) and Co(II) ions, while 2 exhibits the dominant ferromagnetic interactions. [ABSTRACT FROM AUTHOR]

In this study, a heterometallic complex was subjected to the removal of air-pollutants by mediated electrocatalytic reduction (MER) through electro-scrubbing. This paper reports the specific generation of an electro-catalyst, Cu 1+ in Cu 2+ [Ni 2+ (CN) 4 ] heterometallic complex, and its catalytic reduction efficiency in the degradation of gaseous trichloroethylene (TCE). The oxidation/reduction potential (ORP) and the UV–visible spectral results revealed Cu 1+ formation during the electrolysis of Cu 2+ [Ni 2+ (CN) 4 ] in 10 M KOH instead of Ni 1+ . In addition, the electrochemical formation of Cu 1+ (1.9 mM) while in a heterometallic complex was higher than that of the individual Cu 2+ ion (0.47 mM). The electro-generated Cu 1+ [Ni 2+ (CN) 4 ] 1− applied to the removal of gaseous TCE by electro-scrubbing showed almost 100% removal with a gas flow rate of up to 4 L min −1 , which is high enough for use on an industrial scale. In addition, cyclic voltammetry confirmed that TCE removal occurs through MER at a high reaction rate. Both gas and solution phase analyses revealed only CO 2 as the final product, confirming that mineralization is possible by MER. The achievement of 823.8 mg/day removal of TCE under the given conditions brings the present heterometallic approach in electro-scrubbing to a new level in air-pollutant removal. [ABSTRACT FROM AUTHOR]

• The biologically potent monometallic and heterobimetallic complexes of Ni(II) were synthesized. • All the synthesized complexes were characterized by various spectroscopic techniques like UV, FTIR, Mass, 1HNMR , 13CNMR and powder X-ray diffraction studies. • Heterobimetallic complexes showed good antimicrobial activity against a number of pathogenic fungi and bacteria. • The complexes of Ni(II) exhibited effective cytotoxicity activity against MCF-7, HeLa and HaCaT cell lines. • DNA-complex binding studies by UV–vis and fluorescence spectroscopy. Heterobimetallic complexes of Nickel (II) have been synthesized and characterized of the type [Ni(L) 2 (M) 2 R 4 Cl 2 ], where L = 2,6-diaminopyridine (C 5 H 7 N 3), M = Sn, Si, Ti and Zr and R = Ph, Me, C 5 H 5 etc. The monometallic complexes of nickel have been synthesized by using 2,6-diaminopyridine in the presence of NiCl 2 ·6H 2 O dissolved in methanol to form complexes of the type [Ni(L) 2 ]Cl 2. To synthesize heterobimetallic complexes, these synthesized complexes were further processed with main group metal or transition metal dichlorides in a 1:2 molar ratio in MeOH. Elemental analyses, molecular weight calculations, electronic, infrared, magnetic susceptibility, conductivity measurements, mass spectra, 1HNMR , 13CNMR , and powder X-ray diffraction studies have been used to evaluate these synthesized compounds. Using a monometallic complex, the heterobimetallic complexes were synthesized, and an octahedral geometry was perceived for these heterobimetallic complexes. The antimicrobial potency of the synthesized complexes has been evaluated against four different bacterial and three fungal strain at different concentrations. The cytotoxicity activity of these resulting complexes against MCF-7, HeLa and HaCaT cell lines using MTT assay has been scrutinized. Also, the interaction of the reported complexes with calf thymus DNA (CT-DNA) by different techniques revealed that the complexes could bind to CT-DNA by intercalative mode. The binding of the reported complexes to CT-DNA has been investigated using UV–vis and fluorescence spectra. The results indicated a much lower binding affinity of monometallic complex than that of the heterobimetallic complexes. [ABSTRACT FROM AUTHOR]