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By introduction of 2,2′-bipy or 1,10-phen as a second organic ligand, four new zinc(ii) diphosphonate hybrids with mixed ligands, namely, [Zn(2,2′-bipy)(hedpH2)]·0.5H2O (1), [Zn(1,10-phen)(hedpH2)]·H2O (2), [Zn2(1,10-phen)(hedpH2)2]·H2O (3) and [Zn(1,10-phen)(hedpH2)] (4) (hedpH4= 1-hydroxyethylidenediphosphonate, 2,2′-bipy = 2,2′-bipyridine, 1,10-phen = 1,10-phenanthroline) have been synthesized under hydrothermal conditions. Compounds 1and 2adopt a two-dimensional supramolecular network structure containing {[Zn(2,2′-bipy)(hedpH2)]2} or {[Zn(1,10-phen)(hedpH2)]2} units. The neighboring units interdigitate through hydrogen bonding interactions to give a 2D supramolecular network. Compounds 3and 4also have a two-dimensional supramolecular network structure. In compounds 3and 4, 1D Zn–diphosphonate chains were formed. These 1D chains are further connected to adjacent chains through hydrogen bonds to form a 2D supramolecular network. A notable feature for compound 4is the presence of the alternate left- and right-handed helical chains in the structure. The luminescence properties of compounds 1–4have also been studied. [ABSTRACT FROM AUTHOR]

Reaction of the Ir(iii) dimer [(η5-C5Me5)IrCl2]2with PMeXyl2(Xyl = 2,6-C6H3Me2), in the presence of the poorly coordinating base 2,2,6,6-tetramethyl piperidine, gives a chloride complex 1-Cl, resulting from hydrogen chloride elimination involving one of the phosphine benzylic hydrogen atoms and concomitant cyclometallation. Related compounds containing other halide or pseudohalide ligands, 1-Br, 1-Cl, 1-SCN, can be made, the latter featuring S-coordination of the ambidentate thiocyanate to the soft Ir(iii) Lewis acid centre, as suggested by IR data and demonstrated by X-ray crystallography. Hydride 2-H, and alkyl derivatives 3(Me) and 4(CH2SiMe3) can also be prepared from 1-Cland appropriate hydride and alkylating reagents. An interesting H/D exchange chemistry that occurs in the presence of CD3OD has been disclosed for 1-Cl, 1-Brand 2-H. For the halide derivatives, deuterium incorporation takes place into the methylene and methyl sites of their cyclometallated ligand, whereas for 2-Honly the hydride and methylene (Ir–CH2) protons participate in the exchange, which is strikingly accelerated by catalytic amounts of acids. [ABSTRACT FROM AUTHOR]

The reaction of bis(ferrocenyl)methylsilane 1with two carbosilane dendritic cores containing terminal allyl units gives dendrimers functionalized with eight interacting ferrocenyl units. They show two reversible ferrocenyl waves in cyclic voltammetry (CV) and form derivatized Pt electrodes. Platinum electrodes modified with electrodeposited films of these two dendrimers exhibit electrocatalytic activity towards the reduction of oxygen and both oxidation and reduction of hydrogen peroxide. The molecular structure of 1has been determined by single-crystal X-ray diffraction studies. [ABSTRACT FROM AUTHOR]

The synthesis of novel heterobimetallic derivatives of general formula [RuClCp(PPh3)-μ-dmoPTA-1κP:2κ2N,N′-M(acac-κ2O,O′)2] (M = Ni (3), Zn (4); dmoPTA = 3,7-dimethyl-1,3,7-triaza-5-phosphabicyclo[3.3.1]nonane) is described. The preparations of the ruthenium–cobalt analogue (M = Co (2)) and the starting compound [RuClCp(HdmoPTA-κP)(PPh3)](CF3SO3) have been revised and their yield improved. Similar to 2, the solid state structures of 3and 4show that the dmoPTA-P and the dmoPTA-NCH3atoms are involved in the coordination to the {RuCpCl(PPh3)} and {M(acac)2} moieties, respectively. The size of the diffusing units is almost the same for the three binuclear complexes, indicating that they exhibit similar solution structures. The diamagnetic ruthenium–zinc derivative was fully characterized in solution at 193 K by NMR as two diastereomeric pairs of enantiomers (R-Ru, Δ-Zn; R-Ru, Λ-Zn; S-Ru, Δ-Zn; S-Ru, Λ-Zn). Finally, the electrochemical properties of the complexes have been investigated by cyclic voltammetry. [ABSTRACT FROM AUTHOR]

Twelve Pt(ii) complexes with cis-PtP2S2pharmacophores (where P2refers to two monodentate or one bidentate phosphane ligand and S2is a dithiolato ligand) were prepared, characterized and evaluated as potential antiproliferative agents. The various compounds were first studied from the structural point of view; afterward, their solubility properties as well as their solution behaviour were analyzed in detail. Antiproliferative properties were specifically evaluated against A2780 human ovarian carcinoma cells, either resistant or sensitive to cisplatin. For comparison purposes similar studies were carried out on four parent cis-dichloro bisphosphane Pt(ii)complexes. On the whole, the cis-PtP2S2compounds displayed significant antiproliferative properties while the cis-PtP2Cl2(cis-dichloro bisphosphane Pt(ii)) compounds revealed quite poor biological performances. To gain further insight into the molecular mechanisms of these bisphosphane Pt(ii) compounds, the reactions of selected complexes against the model protein cytochrome c were investigated by ESI-MS and their adduct formation explored. A relevant reactivity with cyt c was obtained only for cis-PtP2Cl2compounds, whereas cis-PtP2S2compounds turned out to be nearly unreactive. The obtained results are interpreted and discussed in the frame of the current knowledge of anticancer platinum compounds and their structure–activity-relationships. The observation of appreciable antiproliferative effects for the relatively inert cis-PtP2S2compounds strongly suggests that these compounds will undergo specific activation within the cellular environment. [ABSTRACT FROM AUTHOR]

Pseudooctahedral complexes [MCl3(NtBu)L2] (M = Nb, L = py 1, ½ tmeda 3; M = Ta, L = py 2, ½ tmeda 4) have been studied by spectroscopic methods. By a VT 1H NMR experiment a mutual exchange process between the pyaxand pyfreein the complexes 1–2was observed, whereas 13C and 15N NMR studies showed in the complexes 3–4a tmeda ligand with an axial/equatorial coordination mode. The reaction of 2with 3 equiv of Grignard reagent produces the methathesis products [TaR3(NtBu)] (R = CH2CMeCH25, CH2CHCHCH36) in which 2-methylallyl and 2-butenyl groups appear with a η3- and σ-coordination mode, respectively. When, toluene solutions of the compounds 5–6were treated with 2 equiv of 2,6-dimethylphenylisocyanide the imido bisiminoacyl compounds [TaR(NtBu){C(R)NAr-κ1C}2] (Ar = 2,6-Me2C6H3; R = CH2CMeCH27, CH2CHCHCH38) can be isolated, viaan imido iminoacyl intermediate [TaR2(NtBu){C(R)NAr-κ1C}] (Ar = 2,6-Me2C6H3; R = CH2CMeCH29) as we have observed in the treatment of 5with 1 equiv of isocyanide; however, the analogous reaction between 5and COPh2leads to the formation of the trisalkoxo imido compound [Ta(OCPh2R)3(NtBu)] (R = CH2CMeCH210). All new complexes were studied by IR and multinuclear NMR spectroscopy. [ABSTRACT FROM AUTHOR]

Two {Co3+–Zn2+} heterobimetallic coordination networks have been synthesized utilizing Co3+complex as the building blocks. The structural studies reveal 2D sheet-like networks where the Co3+containing building blocks are connected through Zn2+ions. Two different building blocks generate two unique networks as evidenced by the crystallographic studies and other properties. These networks are shown to catalyze Lewis metal ion assisted Strecker reaction in heterogeneous manner. [ABSTRACT FROM AUTHOR]

The ligand [(1,3-phenylene)bis(methylene)]bis(1-ethyl-imidazol-2-ylidene) (2) (abbreviated as EtCNHCCHCNHCwith CH = central aromatic ring, = CH2spacer) has been synthesised, and isolated, by deprotonation of [(1,3-phenylene)bis(methylene)]bis(1-ethyl-imidazolium) dichloride, Et(CHimid.CHCHimid.)Cl2(1) with LiN(SiMe3)2. This new, remarkably stable NHC dicarbene ligand is quantitatively protonated with HBr to form [(1,3-phenylene)bis(methylene)]bis(1-ethyl-imidazolium) dibromide Et(CHimid.CHCHimid.)Br2(3) and reprotonated slowly enough in MeOH to allow observation of the monoprotonated intermediate 4. Dicarbene 2reacts with S8to give the dithione compound [(1,3-phenylene)bis(methylene)]bis(1-ethyl-imidazol-2-thione) Et[(SC)CH(CS)] (6). Reaction of 2with [IrCl(CO)(PPh3)2] and [Ir(μ-Cl)(cod)]2yielded the mononuclear [Ir(CO)(PPh3)2Et(CHimid.CHCNHC)(PF6)](PF6) (8) and [IrCl(cod)Et(CHimid.CHCNHC)](PF6) (10) complexes, respectively, and the dinuclear complexes [{Ir(CO)(PPh3)2}2Et(μ-CNHCCHCNHC)](PF6)2(7) and [{IrCl(cod)}2Et(μ-CNHCCHCNHC)] (9), respectively, in which 2acts as a bridging, non-pincer type ligand. Only one other Ir(i) complex has been reported before containing a CNHCCHCNHCligand. The structures of 6and 9were determined by X-ray diffraction and depict different conformations of the (1,3-phenylene)bis(methylene) (or xylylene) moiety. The mononuclear Ir complex 9reacted smoothly with [Rh(μ-Cl)(cod)]2and Cs2CO3to generate a rare example of a heteronuclear NHC complex, [IrRhCl2(cod)2Et(μ-CNHCCHCNHC)] (11). [ABSTRACT FROM AUTHOR]

The combination of a [1111]metacyclophane blocked in 1,3-alternate conformation and bearing four imidazole units with MX2(M = Co, Cu, Zn and Hg; X = Cl or Br) complexes leads to the formation of a series of analogous neutral metallamacrotricycles. In all cases, the structure of the binuclear complexes has been studied by X-ray diffraction methods on single crystals. [ABSTRACT FROM AUTHOR]

(S,R)-Indan–ambox ligand and its ruthenium(ii) complex have been prepared and successfully applied to asymmetric hydrogenation of prochiral simple ketones. A wide range of unfunctionalized ketones are reduced by Ru(ii)-indan–ambox catalyst with excellent enantioselectivities (up to 97% ee). [ABSTRACT FROM AUTHOR]

Key elements in this communication are a very efficient microwave synthesis of [RuCp(naphthalene)][PF6], the precursor of [RuCp(CH3CN)3][PF6], and a Pd-catalysed asymmetric hydrogenolysis to afford planar chiral ruthenium complexes with high levels of enantioselectivity using a bulky chiral phosphoramidite ligand. [ABSTRACT FROM AUTHOR]

Heteroleptic complexes, formed selectively by using a 1 : 1 combination of a σ-donor and a π-acceptor ligand, are involved in Rh- and Pd-catalysed reactions. [ABSTRACT FROM AUTHOR]

Abstract: We synthesized a dinuclear Zn2+ complex that is useful as a sensor for ATP in a DMSO/H2O (1:9, v/v) solvent system via a simple indicator displacement assay (IDA). This chromogenic sensor method can be used to analyze 0.1–2.0μM of ATP with no interference from ADP or AMP. [Copyright &y& Elsevier]

In copolymer phosphors with Eu(III), the majority have difficulty in resisting aging by UV light. In this paper, a novel copolymer phosphor with high thermal resistance and good ultraviolet aging resistance was synthesized by radical polymerization from the Eu-complex and siloxane. Intense red emission peaked at 613 nm, corresponding to the D → F transition of Eu(III) ions, was observed under UV excitation. The fluorescence lifetime is calculated as 0.586 ms, with a loss of 0.003 ms after aging for 150 h. The thermal stability shows excellent resistance to high temperature, and the initial decomposition temperature is 153 °C, which meets the requirement of LED operating temperature. The CIE of the LED device is (0.625, 0.308) under excitation at 365 nm. The LED device fabricated with the copolymer and a near-UV LED chip shows bright pure-red emission and good resistance to UV aging. This shows that the copolymer phosphor can be used as an efficient red phosphor in WLEDs. [ABSTRACT FROM AUTHOR]

With the 30 years old first example of a stable group 4 metallocene bis(trimethylsilyl)acetylene (btmsa) complex Cp2Ti(η2‐btmsa) a series of similar complexes like Cp′2M(η2‐btmsa) (M = Ti, Zr; Cp′ = Cp, Cp* as η5‐pentamethylcyclopentadienyl and Cp′2 = rac‐(ebthi) as rac‐1,2‐ethylene‐1,1′‐bis(η5‐tetrahydroindenyl)) represent excellent sources for the generation of the very reactive coordinatively and electronically unsaturated complex fragments [Cp'2M], which were used in many synthetic and catalytic reactions. Examples for this were oresented in several papers and summarized in some reviews. In this update new reactions of group 4 metallocene bis(trimethylsilyl)acetylene complexes towards symmetrically and unsymmetrically α‐dihetero‐substituted alkynes, reactions with other alkynes, di‐ and polyynes to metallacyclopentadienes as well as the conversions of the formed products are summarized. Additionally, novel synthetic applications of the formed metallacyclopentadienes on the basis of the zirconocene bis(trimethylsilyl)acetylene complex Cp2Zr(py)(η2‐btmsa) are highlighted. Reactions with imines, neutral N‐donor ligands, E‐H compounds (E = N, O, P), molecular hydrogen, water, phosphino‐ and aminoboranes, E‐Cl compounds (E = C, P), disilylated germylenes and aryloxy ketones were described. Different self‐assembly reactions to multinuclear complexes by using group 4 metallocene bis(trimethylsilyl)acetylene complexes in C‐C coupling reactions with or without C‐H bond activation to tri‐ or tetranuclear complexes are considered, too. These examples are discussed following the general L‐M‐S principle for stoichiometric and catalytic reactions, whereby different ligands L (L = Cp′ = Cp, Cp*, rac‐ebthi), metals M (M = Ti, Zr, Hf) and substrate substituents S influence the reactivity and the obtained products. An old dog learns new tricks: Group 4 metallocene bis(trimethylsilyl)acetylene complexes Cp′2M(X)(η2‐btmsa) are excellent sources to generate the very reactive complex fragments [Cp'2M]. α‐Heterosubstituted alkynes, di‐ and polyynes, imines, N‐donors, E‐H‐ and E‐Cl‐compounds, hydrogen, water, phosphino‐ and aminoboranes, germylenes, aryloxy ketones, and N‐heterocycles gave many novel products. [ABSTRACT FROM AUTHOR]

Six novel Cd(II) complexes, Cd(bpmi)2Cl2 (1), [Cd(bpmi)2(NO3)2(H2O)]n (2), [Cd2(bpmi)2Cl2(N3)2(CH3OH)2]n (3), [Cd(bpmi)Cl2]n (4), [Cd(bpmi)(SCN)2]n (5) and [Cd(bpmi)(N3)2]n (6), are synthesized by the reaction of different Cd(II) salts with an asymmetric multidentate ligand 1-(benzotriazole-1-methyl)-2-propylimidazole (bpmi). X-ray single-crystal analyses reveal that these complexes show rich structural chemistry ranging from mononuclear (1), one-dimensional (2 and 3), two-dimensional (4 and 5) to three-dimensional (6) structures. These complexes share common features such as they all contain inorganic SBUs and have a high degree of dependence on the corresponding counter anions. In this paper, the fine regulation of counter anions has been discussed in detail. Furthermore, these complexes have been investigated by solid-state UV-vis spectra, thermogravimetric analyses and fluorescence spectra. [ABSTRACT FROM AUTHOR]

In this paper, the formation of Schiff base compounds has been explained by the templating effect of a metal ion modulated by counter anions. It is shown that a dicondensed Schiff ligand can utilize the N2O2 compartment to form a stable copper complex. However, in the presence of a strongly coordinating thiocyanate ion, the dicondensed ligand is converted to the corresponding monocondensed ligand to yield a square planar copper(II) complex coordinated by the NNO donor set of the Schiff base and the terminal thiocyanate coligand. This template approach provides a methodology to trap the monocondensed ligand HL2 [2-((E)-(3-aminopropylimino)methyl)-6-methoxyphenol] as its Cu(II) compound [CuL2(NCS)]. We report herein the crystal structure and spectroscopic studies of this newly synthesized complex. [ABSTRACT FROM AUTHOR]

This study identifies new phosphite-oxazoline ligands that have been successfully applied in the palladium-catalyzed intermolecular asymmetric Heck reaction. The design of the new phosphite-oxazoline ligands derives from a previous successful generation of phosphine-oxazoline ligands, by replacing the phosphine group with several π-acceptor biaryl phosphite moieties. With these simple modifications, the new phosphite-based ligands, unlike previous phosphine-oxazoline, not only present a modular design with numerous potential phosphite groups available, but they are also air-stable solids, which can be made in the same number of synthetic steps as the phosphine analogues. The substitution of the phosphine by a biaryl phosphite group extended the range of substrates and triflates sources that can be coupled with regio-, enantioselectivities and activities comparable to the few best ones reported. In addition, the ligands that provided the best selectivities contained an isopropyl oxazoline moiety instead of the tert-butyl group found in the related phosphine-oxazoline ligands, which is made from a much more expensive precursor. In this paper we have also carried out kinetic studies and a Hammett plot analysis to determine the rate determining step of this system in the regime of interest. We suggest a likely explanation for the fast Heck reaction of the phosphite-oxazoline catalysts. [ABSTRACT FROM AUTHOR]

Our quest for ligands toward the synthesis of functional metal string complexes started from α‐pyridylamido anions. With the modulation of naphthyridylamido anions, the ligands carry less negative charge to be balanced and, thus, to some extent, can tune the oxidation state of the metal centers and the strength of metal–metal interactions. For example, the formation of Ni23+, a mixed‐valence moiety, has been demonstrated. In this paper, high‐bond‐order units of M2 (Mo2 or Ru2) and Ni23+ are introduced and supported by four equatorial ligands of the bisnaphthyridylamido anion (bna−). The resulting compounds are [Ni2Mo2Ni(bna)4Cl2](PF6)3 (1), [Ni2Mo2Ni(bna)4(NCS)2](PF6)3 (2), and [Ni2Ru2Ni(bna)4Cl2](ClO4)3 (3). X‐ray crystallography reveal quadruply bonded characteristics with Mo–Mo distances of 2.133(2) and 2.109(2) Å for 1 and 2, respectively. The Ni2 moieties have a short Ni–Ni distance of 2.331(5) for 1 and 2.334(4) Å for 2, suggesting the formation of mixed‐valence Ni23+ units. It appears that there are no significant metal–metal interactions between Mo2 and its neighboring Ni centers. Characterization using magnetism, voltammetry, electronic absorption, and single‐molecule conductance, however, shows significant influence of Mo2 on the properties of the metal string complexes. [ABSTRACT FROM AUTHOR]

This paper contains the synthesis of the new 2-morpholinoethyl substituted bis-(NHC)Pd(II) complexes and their catalytic activity in direct arylation reaction. The new bis-(NHC)Pd(II) complexes have been prepared from Ag(I)NHC complexes by using transmetallation method. The new bis-(NHC)Pd(II) complexes have been characterized by using H NMR, C NMR, FTIR spectroscopy and elemental analysis techniques. Molecular and crystal structure of the complex 1a and its ligand ( N-benzylbenzimidazole) were obtained by single crystal X-ray diffraction method. The new bis-(NHC)Pd(II) complexes exhibit activity in the reaction after being examined as catalysts in the direct arylation (C-H activation) reaction. Graphical Abstract: [ABSTRACT FROM AUTHOR]

A series of 16 complexes of 1,2-bis(benzothiazolyl) benzene and 1,2-bis(benzothiazolyl)-4-methyl benzene compounds with Ti(IV), Zr(IV), V(III), Fe(III), Fe(II), Co(II), Ni(II) and Cu(II) were synthesized and characterized. After activation with methylalumoxane (MAO), these complexes showed variable activities towards ethylene polymerization. The polymerization activities of the catalyst system 3, 5, 7 and 15/MAO were investigated under different polymerization conditions. The highest activity 625 [Kg PE / mol Cat. H] is obtained by the catalyst system 5/MAO at 50 °C and cocatalyst concentration of 1000 equivalents. The produced resins showed high molecular weights associated with broad or even bimodal molecular weight distributions for all catalysts systems except the polymers produced with nickel catalysts 9 and 17/MAO. [ABSTRACT FROM AUTHOR]

In spite of a large number of antibiotics and chemotherapeutics available for medical use, the emergence of old and new in the last decades revealed a substantial medical need for new classes of . In this paper we report the synthesis, characterization by elemental analysis, Fourier transform infrared and spectroscopies, and antifungal properties of two heteroleptic complexes of albendazole (albz) with Ag(I), using KSCN and o-phenanthroline (phen) as the second ligand, respectively. Both complexes showed a moderate antifungal activity with all the assayed fungi, mainly Candida albicans and Candida tropicalis, that showed no activity against albendazole. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The manuscript describes the results of the pioneering work of the interaction of Pt(II) and Pd(II) metal ions, with nucleosides, aiming to understand the detailed mechanism, by which they occur. These studies resulted in a number of scientific papers that were published in the early seventies (1970–75). The present note is not a general review paper, but it is mainly limited to the reporting of the reactions studied for the first time. Some references to recent papers, addressing the possibility of Pt chelating of guanosine derivatives, are presented. The results refer to coordination sites and the synthesis of new complexes of metal ions with nucleobases. [ABSTRACT FROM AUTHOR]

The instant and on-site detection of trace aqueous nitrite ions still remains a challenge for environmental monitoring and protection. In this work, we synthesized water-soluble striking fluorescent Cu nanoclusters (Cu NCs) by a green, simple, one-pot and stabilizer-free chemical reduction method. The fluorescence (FL) of the obtained Cu NCs can be selectively and efficiently quenched by the nitrite ions through the oxidation of Cu (0) atoms to Cu (I) in the core of Cu NCs. Under optimal conditions, two excellent linear relationships between the FL quenching degree of the Cu NCs and the concentrations of nitrite ions in the range of 0.0125–125 μM and 125–5000 μM with a low detection limit of 3.6 nM were obtained. More importantly, the portable paper-based sensor has been explored for visual detection of trace nitrite ions in aqueous solution by the appearance of different degrees of blue FL under a UV lamp. The very simple and effective strategy reported here should facilitate the development of portable and reliable FL chemosensors for nitrite ions in pollution control. [ABSTRACT FROM AUTHOR]

The present paper deals with the synthesis and characterization of metal complexes of Schiff base derived from xipamide, a diuretic drug. The bidentate ligand is derived from the inserted condensation of 5-aminosulfonyl-4-chloro-N-2,6-dimethyl phenyl-2-hydroxybenzamide (Xipamide) with salicylaldehyde in a 1:1 molar ratio. Using this bidentate ligand, complexes of Hg(II), Zn(II), and VO(IV) with general formula ML2 have been synthesized. The synthesized complexes were characterized by several techniques using molar conductance, elemental analysis, magnetic susceptibility, FT-IR spectroscopy, electronic spectra, mass spectra, and particle size analysis. The elemental analysis data suggest the stoichiometry to be 1:2 [M:L]. All the complexes are nonelectrolytic in nature as suggested by molar conductance measurements. Infrared spectral data indicate the coordination between the ligand and the central metal ion through deprotonated phenolic oxygen and azomethine nitrogen atoms. Spectral studies suggest tetrahedral geometry for Hg(II), Zn(II) complexes, and square pyramidal geometry for VO(IV) complex. The pure drug, synthesized ligand, and metal complexes were screened for their antifungal activities against Aspergillus niger and Aspergillus flavus. The ligand and its Hg(II) and VO(IV) complexes were screened for their diuretic activity too. [ABSTRACT FROM AUTHOR]

A variety of bismuth complexes have been extensively explored in biomedical applications. The well-known low toxicity and environmental friendliness of bismuth salts make them valuable for large-scale synthesis of various bismuth-based complexes, which become more significant as active pharmaceutical ingredients of medical products. Bismuth complexes have been widely and preferably used in biomedicine with satisfactory therapeutic effect, which is highlighted in this review. However, their synthesis methods have been scarcely summarized. The classification of the main synthesis methods of bismuth complexes has been done here, followed by updates of the relevant advances concerning applications in biomedicine such as therapeutic effect on gastrointestinal diseases, antimicrobial, and anticancer activities, and the description of the side effect and biotoxicity resulting from long-term use of bismuth as well. Bismuth containing metal–organic frameworks, newly developed bismuth-based materials, are also discussed here, becoming a hot research topic recently. An outlook for future study on the potential use of bismuth complexes in biomedicine is provided in the end. This paper reviews the synthesis and biomedical applications of bismuth complexes with unusually low toxicity and excellent clinical performances, summarizes their main synthesis methods, and biomedical applications as drugs for the therapeutic treatment of gastrointestinal disease,Helicobacter pyloriinfection, and various cancers; especially, describes the development of bismuth-based MOFs in the drug delivery and potential application in cancer treatment. [ABSTRACT FROM PUBLISHER]

A new simple methodology to synthesize NH 4 V 3 O 8 has been reported in this paper. The reaction of NH 4 VO 3 with I 2 or Br 2 under mild hydrothermal conditions prepares NH 4 V 3 O 8 . The title compound was characterized by element analysis, infrared spectrum, inductively coupled plasma atomic emission spectrum, X‐ray powder pattern at room temperature, and thermal analysis was studied in the range of 28–800°C. [ABSTRACT FROM AUTHOR]

In this paper, we report that a known dinuclear Fe complex, [tpa(H2O)FeOFe(H2O)tpa](ClO4)4(tpa: tris(2-pyridylmethyl)amine), is an efficient catalyst toward organic sulfide oxidation in the presence of urea-hydrogen peroxide. [ABSTRACT FROM AUTHOR]

This paper presents a facile and rapid synthesis route of metallic Ni and Co nanocrystallites at ~150 °C in the mixture composed of the corresponding metal nitrates and 1,3-propanediol, as reducing agent. The metal oxides NiO, CoO, CoO nanocrystallites were, also, successfully synthesized by thermal decomposition at 300 °C of the hydroxycarboxylate coordination products, obtained in the redox reaction between 1,3-propanediol and Ni(II) and Co(II) nitrates. The formation of the Ni(II) and Co(II) hydroxycarboxylate complexes depends on the diol which generates the carboxylate anion, the transition metal and the process parameters. Ni(II) and Co(II) nanocomposites were also synthesized by thermal decomposition of the complex combinations formed within the pores of the hybrid silica gels. One of the purposes of the present study was to investigate the phase constitution of the composites obtained in similar synthesis conditions, from Ni(II) and Co(II) complex combinations embedded in silica gels. These gels were submitted to various thermal treatments and the changes occurring during these treatments were described by X-ray diffraction. Thermal analysis is an excellent tool for the study of the processes implied in the formation and decomposition of the Co(II) and Ni(II) carboxylate complexes. X-ray diffraction evidenced the nanometer sized metal and/or metal oxide phases. [ABSTRACT FROM AUTHOR]

A Schiff base was synthesized by reaction of 1,3-diamino-2-propanol and 5-bromo-2-hydroxy benzaldehyde. The Schiff base N,N′-bis(5-bromo-salicylidene)-2-hydroxy-1,3-propanediamine ( BSHP) was characterized by elemental analysis, H NMR, C NMR, IR, UV-Vis spectral studies. The complexation of iron with BSHP was investigated spectrophotometrically. The extraction of iron from oil phase to aqueous phase was carried out with BSHP. Extraction conditions were optimized using central composite design. Optimum extraction conditions were found to be 32°C, 2 mL/g for the ratio of the volume of the Schiff base solution to the amount of oil, and 11 min for the stirring time. The method has been validated by using oil based metal standard, obtaining satisfactory results. The limit of detection ( LOD) of the improved method is 0.04 μg/g. It has been applied to analysis of different oil samples. The concentrations of iron in olive, sunflower and corn oils were found to be 0.65 ± 0.02, 0.41 ± 0.01, 0.36 ± 0.03 μg/g, respectively. A simple, cheap, rapid, efficient, sensitive and accurate alternative analytical method for the iron determination in oils has been presented in this paper. [ABSTRACT FROM AUTHOR]

In this paper, we report the synthesis and physico-chemical investigation of two uranyl–salophen receptors, bearing either one or two anthracenyl moieties appended to the salophen skeleton. Despite the presence of the anthracenyl fluorophores, no fluorescence emission was detected. Photophysical data and cyclic voltammetric experiments show that photoinduced electron transfer from the anthracene-localised first singlet excited state to the metal centre is strongly exergonic, thus suggesting that this is the main fluorescence quenching mechanism in these complexes. The investigated compounds are photoreactive upon UV irradiation, yielding either anthracene photooxidation or photodimerisation products depending on the specific complex and the experimental conditions. [ABSTRACT FROM PUBLISHER]

Complexes of Cr(III), Fe(III) and Co(III) with biacetyl mono oxime phenoxy acetyl hydrazone(BAMPxH), bibenzoyl monoxime phenoxy acetyl hydrazone(BBMPxH) have been isolated and characterized by analytical data, molar conductance, magnetic measurement, electronic spectra and thermo-gravimetric analysis. Cr(III), Fe(III) and Co(III) complexes were found to have octahedral structure. This paper describes the preparation and characterization of transition metal complexes of biacetyl monoxime phenoxy acetyl hydrazone (BAMPxH) and bi benzoyl monoxime phenoxy acetyl hydrazone (BBMPxH). The stereo-chemistry of the coordination compounds has been confirmed on the basis of electronic spectral and magnetic moment studies. Racah's inter-electronic parameter (B), Cubic Ligand field splitting parameter (10Dq) and Nephelauxetic ratio (β), g, λ, h have also been calculated and found that the values are in accordance with the stereo-chemical structure of the coordination compounds. The ligands BAMPxH and BBMPxH are of greater importance since they have ability to chelate metal ion through nitrogen/or oxygen donor centers. Thess ligands can form such type of complexes which are biologically important. Such metal complexes show interesting and important characteristics, especially in areas such as semiconductors, heat resistance materials and gas separators. There has been growing interest for polymeric compounds which are coordinated between ligands and transition metal complexes. [ABSTRACT FROM AUTHOR]

An efficient and facile synthesis of polydentate ligand pyridylpyrimidine-2-amine via a one-pot reaction of different aromatic aldehydes, 2-acetylpyridine and guanidine carbonate, in the presence of NaOH under solvent-free conditions, is reported. These compounds have four N-donors and they are classic polydentate ligands of many metal ions. Due to employing a one-pot, multicomponent reaction, this method offers several advantages including easy experimental work-up procedure, and lower cost, short reaction time, and especially high yields of products. This paper therefore develops a practical and convenient process for the synthesis of these ligands. [ABSTRACT FROM AUTHOR]

A number of dioxouranium (VI), UO22+ complexes of Schiff base and monodithiocarbamate ligands have been synthesized and characterized. Antimicrobial activities of these complexes have been studied. The results of inhibition zones of the selected microorganisms showed that all complexes exhibited mild to prominent activities against the pathogens tested herein. [ABSTRACT FROM AUTHOR]

X3Al-YC4H4 (X = H, F, Cl and Br; Y = O in furan, Y=NH in pyrrole, and Y = S in thiophen) have been investigated as donor-acceptor complex types using the DFT level of theory. Both staggered and eclipsed conformations have been examined. For all complexes, the first one is found to be favored. The DFT results including the BSSE contribution show that fluoro complexes are more stable than the others. The interaction diagrams prove that the evolution of complexation energy depends on the coordination mode. In fact, this is a simple "HOMO-LUMO" interaction for X3Al-YC4H4 complexes. This quantum chemistry analysis of the X3Al-YC4H4 donor-acceptor complexes shows no correlation with the charge transfer. [ABSTRACT FROM AUTHOR]

Abstract: Six new Cu(II), Ni(II), and VO(II) complexes (1–6) with Schiff base 1-phenyl-2,3-dimethyl-4-(1H-indole-3-carboxaldehyde)-3-pyrazolin-5-one (HL) were synthesized. The Schiff base was prepared through the condensation of 1-phenyl-2,3-dimethyl-4-amino-3-pyrazolin-5-one (antipyrine) with 1H-indole-3-carboxaldehyde. The new obtained compounds were characterized by 1H NMR, 13C NMR, UV–VIS, IR, EPR spectroscopy, elemental analysis, molar electric conductibility, magnetic susceptibility and thermal gravimetric analysis. In addition, the structure of the ligand HL has been determined by X-ray diffraction methods. The biological activity of complex compounds was investigated in terms of antibacterial effect on prokaryotic cells, by using paper disc diffusion technique, and for antiproliferative effect on eukaryotic cells, by monitoring mitotic activity in timelapse videomicroscopy experiments. The compounds were screened for their antibacterial activity against gram-positive bacteria (Staphylococcus aureus var. Oxford 6538, Klebsielle pneumoniae ATCC 100131 and Legionella monocytogenes ATCC 35182), gram-negative bacteria (Escherichia coli ATCC 10536, Pseudomonas aeruginosa ATCC 9027 and Salmonella typhimurium ATCC 14028) and anti-fungal activity (Candida albicans and Aspergillus flavus) using paper disc diffusion technique. The minimum inhibitory concentrations (MICs) of the compounds were also determined by agar streak dilution method. Compounds 3 and 4 proved to be the most effective as antibacterial agents. The antiproliferative activity was investigated by counting the number of mitoses for HeLa, and MCF7 cells. No significant antiproliferative effect was noted for HL and complex 2, for both used cell types. For complexes 1 and 3 complete inhibition of cell proliferation was observed in the case of HeLa cells, while the effects on MCF7 cell proliferation were lower. In conclusion, six new complex compounds were synthesized, and their biological activity investigated on both prokaryotic and eukaryotic cells, proving that some of them could be putative therapeutic substances. [Copyright &y& Elsevier]

Uracil, one of the four RNA bases is a vital component in the complex processes of molecular genetics. The correct functioning of these processes depends on the types of bonds formed by uracil with the surroundings. This communication elaborates the versatile potential of 1,3-dimethyl-6-aminouracil (L) to form its 5-, 6- position substituted derivatives with different significant molecular packing behaviours. Presently, five crystals (L-L) have been synthesised and their crystallographic architectures are glimpsed in this paper. Analysis of crystal packing shows supra-molecular behaviours through hydrogen bonding and π-π interactions among the molecules in maintaining the integrity of the structures. The ligand 6,6'-diamino-1,1',3,3'-tetramethyl-5,5'-(benzylidene)bis[pyrimidine-2,4(1 H,3 H)-dione] was observed to be stabilised in a helical arrangement. Graphical Abstract: Versatile potential of 1, 3-dimethyl-6-aminouracil to form its 5-, 6- position substituted derivatives e.g. 6,6'-diamino-1,1',3,3'-tetramethyl-5,5'-(benzylidene)bis[pyrimidine-2,4(1 H,3 H)-dione] in a helical arrangement.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

This paper reports a facile one-step synthesis of two ternary lanthanide complexes via room temperature solid-state reactions of lanthanide chloride hydrates with two ligands, potassium sorbate (PS), and 8-hydroxyquinoline (8-hq). The structural features, composition, and the morphologies of two complexes are characterized by elemental analysis, UV-Vis, FT-IR, XRD, SEM, and EDX. The thermal property of two ternary lanthanide complexes was also investigated. UV-Vis and FT-IR results confirm the coordination of lanthanide ion with two ligands. XRD results show that signals of complexes are not from reactants, and are believed to originate from the corresponding ternary lanthanide complex. [ABSTRACT FROM AUTHOR]

In this paper, we report the preparation of highly stable gold nanoparticles/poly(3,4-ethylendioxythiophene) nanocomposites by a one-pot chemical route in aqueous medium without surfactants to increase the solubility of the monomer (3,4-ethylendioxythiophene, EDOT) or to stabilize gold nanoparticles (Au NPs). The generation of the nanocomposite was followed by UV-Visible transmission spectroscopy combined with multivariate curve resolution alternating least squares analysis to deconvolute the individual spectra of the different species generated in the synthesis: oligomers, polymer and gold nanoparticles. The plasmon band observed at 530 nm during the synthesis step indicates the generation of gold nanoparticles. The influence of monomer and metal precursor concentration and their concentration ratios on Au NP size were analyzed. The electrochromic properties of the composite were investigated by UV-Visible absorption spectroelectrochemistry, being mainly related to polymer oxidation and reduction. The main difference observed is the hypsochromic shift of the polymer spectra due to the gold nanoparticles inside the polymer. Multicyclic spectroelectrochemical experiments evidence a high stability and adhesion of the nanocomposite. [ABSTRACT FROM AUTHOR]

Highlights • Core-shell structured inorganic nanocomposite as photocatalyst. • Photocatalytic reduction of CO 2 to methanol under visible light. • Ni/NiO core-shell structured semiconductor as photoactive support. • Selective reduction of CO 2 to methanol. • Consistent efficiency and facile recovery for recycling. Abstract The present paper describes the first successful synthesis of an inorganic nanocomposite by grafting of cobalt (II) phthalocyanine (CoPc) on the core-shell Ni/NiO (NNO) semiconductor for the photocatalytic reduction of CO 2 to methanol under visible illumination using triethylamine as a sacrificial donor. The synthesised photocatalyst exhibited a remarkable enhancement in the yield of methanol as compared to the semiconductor Ni/NiO and CoPc for CO 2 reduction under identical conditions. The maximum yield of methanol was found to be 3641.2 μmol/g with the conversion rate of 151.7 μmol g−1 h−1 which was much higher than that observed with CoPc and semiconductor alone under identical experimental conditions. Furthermore, the synthesised nanocomposite showed superior activity as compared to the previously reported organic semiconductor bound cobalt complex photocatalyst. The composite photocatalyst was found to be highly stable which showed consistent recyclability for four runs without any significant loss in activity. [ABSTRACT FROM AUTHOR]

In this paper, the synthesis and characterization of some imidazole-based gold-selenolates are described. This study indicates that the nature of selenolate plays an important role in ligand exchange reactions in gold(I) selenolates. Furthermore, the reactivity of imidazole-based gold(I) selenolates toward nucleophiles such as selenols and phosphines is strikingly different from that of the N,N-dimethylaminobenzylamine-based gold(I) complexes. The presence of Se⋯N non-bonded interactions in N,N-dimethylaminobenzylamine-based gold(I) complexes modulates the reactivity of Au(I) center towards incoming nucleophiles. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

This paper examines the mechanisms of metal sulfide formation with the participation of metal complexes with thiourea. We have synthesized cadmium sulfide nanoparticles using carbon-chain polymers as stabilizers and investigated the effect of the polymer matrix on the properties of the nanoparticles. [ABSTRACT FROM AUTHOR]

The reactions of 3,3′-bis(5-mercapto-1,2,4-triazole) with Co(ii) and Ni(ii) ions, respectively, gave two nanospheric mixed-valence icosanuclear cage-like complexes [M20L12](SO4)2·6DMF·CH3OH·3H2O (M = Co, 1; Ni, 2) with the in situ generated oxalyldithiosemicarbazide (H4L) as ligand. The eight octahedral M(ii) ions and twelve square-planar M(iii) ions in the two complexes are linked by twelve three-connecting linkers of L4− to build an icosanuclear [MII8MIII12L12]4+ nanocage with an inner cubic MII8 cage core. Their cage skeletons are stable in water. The sulphate anions reside over the cage portals. The magnetic measurements of the two complexes revealed the presence of dominant antiferromagnetic interactions between the metal ions in both complexes. [ABSTRACT FROM AUTHOR]

The synthesis, spectroscopic characterization, cytotoxic activity and DNA binding evaluation of seven new dinuclear platinum(ii) complexes Pt1–Pt7, with the general formula [{Pt(L)Cl}2(μ-1,5-nphe)](ClO4)2 (1,5-nphe is 1,5-naphthyridine; while L is two ammines (Pt1) or one bidentate coordinated diamine: ethylenediamine (Pt2), (±)-1,2-propylenediamine (Pt3), trans-(±)-1,2-diaminocyclohexane (Pt4), 1,3-propylenediamine (Pt5), 2,2-dimethyl-1,3-propylenediamine (Pt6), and 1,3-pentanediamine (Pt7)), were reported. In vitro cytotoxic activity of these complexes was evaluated against three tumor cell lines, murine colon carcinoma (CT26), murine mammary carcinoma (4T1) and murine lung cancer (LLC1) and two normal cell lines, murine mesenchymal stem cells (MSC) and human fibroblast (MRC-5) cells. The results of the MTT assay indicate that all investigated complexes have almost no cytotoxic effects on 4T1 and very low cytotoxicity toward LLC1 cell lines. In contrast to the effects on LLC1 and 4T1 cells, complexes Pt1 and Pt2 had significant cytotoxic activity toward CT26 cells. Complex Pt1 had a much lower IC50 value for activity on CT26 cells compared with cisplatin. In comparison with cisplatin, all dinuclear Pt1–Pt7 complexes showed lower cytotoxicity toward normal MSC and MRC-5 cells. In order to measure the amount of platinum(ii) complexes taken up by the cells, we quantified the cellular platinum content using inductively coupled plasma mass spectrometry (ICP-QMS). Molecular docking studies performed to evaluate the potential binding mode of dinuclear platinum(ii) complexes Pt1–Pt7 and their aqua derivatives W1–W7, respectively, at the double stranded DNA showed that groove spanning and backbone tracking are the most stable binding modes. [ABSTRACT FROM AUTHOR]

Silver complexes involving vinyltrifluoroborate, (IPr)Ag(CH2=CHBF3) (4), [(IPr)2Ag][CH2=CHBF3] (5), (SIPr)Ag(CH2=CHBF3) (6) and (IPr*)Ag(CH2=CHBF3) (7) have been synthesized by using (NHC)AgNO3 [NHC = IPr (1), SIPr (2) and IPr* (3)] and K(CH2=CHBF3) in a metathesis process. NMR spectroscopic details of 1–7 and X‐ray crystal structures of compounds 5–7 as well as that of a precursor (IPr)AgNO3 are reported. Compounds 6 and 7 are more stable in solution compared to 4 (which forms 5) indicating a supporting ligand effect in the stability of monomeric (NHC)Ag(CH2=CHBF3). Calculated metal–ligand binding energies show that [CH2=CHBF3]− is a significantly better ligand for AgI than CH2=CH2 or isoelectronic CH2=CHCF3. IPr, SIPr and IPr* carbenes coordinate to Ag(CH2=CHBF3) moiety forming silver adducts 4, 6 and 7, with binding energies of about –72.1, –72.1 and –83.8 kcal/mol, respectively. The C=C bond length of [CH2=CHBF3]− (calculated value of 1.341 Å) increases upon coordination to the silver ion. Experimental data show a similar trend for structurally characterized 6 and 7. Electrostatic attraction dominates the bonding between the alkene ligand [C2H3BF3]− and the metal fragments [Ag(IPr)]+ and [Ag(SIPr)]+ in 4 and 6. The strongest orbital interaction involves σ‐donation from the occupied π‐orbital of the [C2H3BF3]− ligand to the vacant orbital of the metal fragment, while AgI→[C2H3BF3]− π‐backbonding is relatively weak but not insignificant. Unsaturated organotrifluoroborate [CH2=CHBF3]– is an excellent ligand for d‐block metal ions as evident from the isolation of two silver(I) complexes, (SIPr)Ag(CH2=CHBF3) and (IPr*)Ag(CH2=CHBF3). [ABSTRACT FROM AUTHOR]

In this work the synthesis, photochemistry, and streptavidin interaction of new [Ru(tpy)(bpy)(SRR′)](PF6)2 complexes where the R′ group contains a free biotin ligand, are described. Two different ligands SRR′ were investigated: An asymmetric ligand 1 where the Ru‐bound thioether is a N‐acetylmethionine moiety linked to the free biotin fragment via a triethylene glycol spacer and a symmetrical ligand 2 containing two identical biotin moieties. The coordination of these two ligands to the precursor [Ru(tpy)(bpy)Cl]Cl was studied in water at 80 °C. In such conditions the coordination of the asymmetric ligand 1 occurred under thermodynamic control. After the reaction, a mononuclear and a binuclear complex were isolated. In the mononuclear complex, the ratio of methionine‐ {[6](PF6)2} vs. biotin‐bound {[7](PF6)2} regioisomer was 5.3 and the free biotin fragment of [6](PF6)2 allowed to purify it from its isomer [7](PF6)2 at small scales using avidin affinity chromatography. Coordination of the symmetrical ligand 2 afforded [Ru(tpy)(bpy)(2)](PF6)2 {[8](PF6)2} in synthetically useful scales (100 mg), good yield (82 %), and without traces of the binuclear impurity. In this complex, one of the biotin remains free whereas the second one is coordinated to ruthenium. Photochemical release of ligand 2 from [8](PF6)2 occurred upon blue light irradiation (465 nm) with a photosubstitution quantum yield of 0.011 that was independent of the binding of streptavidin to the free biotin ligand. A new synthetic strategy is presented for preparing photoactivated chemotherapeutic ruthenium compounds functionalized with a free biotin group. The free biotin fragment, which is bound to ruthenium via a thermally stable Ru–S bond, can still bind to streptavidin. Blue light irradiation resulted in the cleavage of the biotin‐bearing protecting ligand, thus liberating the ruthenium aqua compound. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Synthesis and theoretical studies of a new Pd complex with a cyclophosphazene-based ligand for Suzuki-Miyaura reactions. Abstract This paper describes the synthesis of a cyclophosphazene-based diphenylphosphine ligand and a new Pd(0) complex. Infrared spectroscopy (ATR-IR), ESI+-MS, 31P, 1H and 13C NMR, Raman, WD-XRF, ICP-OES and TGA analysis show the coordination of two palladium atoms per unit of cyclophosphazene. A semiempirical calculation method was employed to find the lowest energy structure among the possible ones and Density Functional Theory (DFT) was used to optimize the found structure and obtain its bond angles, dihedral angles, bond lengths, atomic distances, and to calculate the vibrational spectrum (PBE/def2-TZVP(-f)). The new Pd complex showed activity in Suzuki-Miyaura cross-coupling reactions with halobenzenes and phenylboronic acid, tolerating different functional groups. [ABSTRACT FROM AUTHOR]

Abstract  In this paper, three new metal-organic frameworks, synthesized by hydrothermal technique, are described. The compounds crystallize in triclinic space group P − 1 with cell parameters, respectively equal to (1) [La(H2O)3(dipic)]2(C2O4) · 2H2O a = 7.9990(1) Å, b = 8.3380(4) Å, c = 9.6180(5) Å, α = 98.194(5)°, β = 100.438(3)°, γ = 102.437(3)°, (2) [Eu(H2O)2(C2O4)]2(dipic) · 3H2O a = 8.2170(6) Å, b = 10.5900(8) Å, c = 13.0670(3) Å, α = 93.951(3)°, β = 103.393(5)°, γ = 107.797(6)°, and (3) [Ce3(dipic)3(Hdipic)(SO4)(H2O)3] · 4H2O a = 11.655(1) Å, b = 12.886(1) Å, c = 16.139(2) Å, α = 106.369(8)°, β = 92.90(1)°, γ = 115.787(7)°. They differ by their dimensionality mono-dimensional for (1), tri-dimensional for (2) and bi-dimensional for (3). Index Abstract  Compound (3) [Ce3(dipic)3(Hdipic)(SO4)(H2O)3] · 4H2O crystallizes in a three dimensional network because of the strong hydrogen bonds and the overlap between some pyridine rings of dipic ligand. [ABSTRACT FROM AUTHOR]

The paper reports on the synthesis, crystal structure, differential scanning calorimetry (DSC) and magnetic properties of a spin crossover salt of formula [Fe(bpp)2](cis,cis-1,3,5-Hchtc)·5.5 H2O (1) (bpp = 2,6-bis(pyrazol-3yl)pyridine; cis,cis-1,3,5-Hchtc = monoprotonated cyclohexanetricarboxylate dianion). The salt shows a porous structure with water molecules sitting in the channels. The electronic configuration of the Fe2+ions is high-spin (HS). Desolvation of 1yields a material exhibiting an abrupt spin crossover with a thermal hysteresis loop located near room temperature (T1/2↑ = 319 K and T1/2↓ = 309 K). Rehydration of this desolvated salt yields an essentially low-spin (LS) material. This is the first example of a series of hydrogen-bonded porous structures that combine a Fe(bpp)2spin crossover unit acting as a hydrogen-bond donor and polycarboxylate anions acting as hydrogen-bond acceptors with different connectivities. [ABSTRACT FROM AUTHOR]