Reactions of Cadmium(II) Halides and Di-2-Pyridyl Ketone Oxime: One-Dimensional Coordination Polymers.

The coordination chemistry of 2-pyridyl ketoximes continues to attract the interest of many inorganic chemistry groups around the world for a variety of reasons. Cadmium(II) complexes of such ligands have provided models of solvent extraction of this toxic metal ion from aqueous environments using 2-pyridyl ketoxime extractants. Di-2-pyridyl ketone oxime (dpkoxH) is a unique member of this family of ligands because its substituent on the oxime carbon bears another potential donor site, i.

Polyfluorinated Naphthalene-bis-hydrazimide for Solution-Grown n-Type Semiconducting Films.

Naphthalene tetracarboxylic diimides (NDIs), possessing low-lying and tunable LUMO levels, are of wide interest for their aptitude to provide cost-effective, flexible, and environmentally stable n-type organic semiconductors through simple solution processing. NDI-based aromatic hydrazidimides are herein studied in relation to their chemical and environmental stability and as spin-coated stable thin films. In the case of the pentafluorinated residue, these were found to be crystalline, highly oriented, and molecularly flat (roughness = 0.

Forcing Twisted 1,7-Dibromoperylene Diimides to Flatten in the Solid State: What a Difference an Atom Makes.

Perylene diimides (PDI) are workhorses in the field of organic electronics, owing to their appealing n-semiconducting properties. Optimization of their performances is widely pursued by bay-atom substitution and diverse imide functionalization. Bulk solids and thin-films of these species crystallize in a variety of stacking configurations, depending on the geometry of the stable conformation of the polyaromatic core.

Confirming the Molecular Basis of the Solvent Extraction of Cadmium(II) Using 2-Pyridyl Oximes through a Synthetic Inorganic Chemistry Approach and a Proposal for More Efficient Extractants.

The present work describes the reactions of CdI with 2-pyridyl aldoxime (2paoH), 3-pyridyl aldoxime (3paoH), 4-pyridyl aldoxime (4paoH), 2-6-diacetylpyridine dioxime (dapdoH) and 2,6-pyridyl diamidoxime (LH). The primary goal was to contribute to understanding the molecular basis of the very good liquid extraction ability of 2-pyridyl ketoximes with long aliphatic chains towards toxic Cd(II) and the inability of their 4-pyridyl isomers for this extraction. Our systematic investigation provided access to coordination complexes [CdI(2paoH)] (), {[CdI(3paoH)]} (), {[CdI(4paoH)]} () and [CdI(dapdoH] ().

Dinuclear Lanthanide(III) Complexes from the Use of Methyl 2-Pyridyl Ketoxime: Synthetic, Structural, and Physical Studies.

The first use of methyl 2-pyridyl ketoxime (mepaoH) in homometallic lanthanide(III) [Ln(III)] chemistry is described. The 1:2 reactions of Ln(NO)·HO (Ln = Nd, Eu, Gd, Tb, Dy; = 5, 6) and mepaoH in MeCN have provided access to complexes [Ln(OCMe)(NO)(mepaoH)] (Ln = Nd, ; Ln = Eu, ; Ln = Gd, ; Ln = Tb, ; Ln = Dy, ); the acetato ligands derive from the Ln-mediated hydrolysis of MeCN. The 1:1 and 1:2 reactions between Dy(OCMe)·4HO and mepaoH in MeOH/MeCN led to the all-acetato complex [Dy(OCMe)(mepaoH)] ().

Indium(III) in the "Periodic Table" of Di(2-pyridyl) Ketone: An Unprecedented Transformation of the Ligand and Solid-State In NMR Spectroscopy as a Valuable Structural Tool.

Reactions of di(2-pyridyl) ketone, (py)CO, with indium(III) halides in CHNO have been studied, and a new transformation of the ligand has been revealed. In the presence of In, the C═O bond of (py)CO is subjected to nucleophilic attack by the carbanion :CHNO, yielding the dinuclear complexes [InX{(py)C(CHNO)(O)}] (X = Cl, ; X = Br, ; X = I, ) in moderate to good yields. The alkoxo oxygens of the two η:η:η-(py)C(CHNO)(O) ligands doubly bridge the In centers and create a {In(μ-OR)} core.

The First Use of a ReX Synthon to Modulate Fe Spin Crossover via Supramolecular Halogen⋅⋅⋅Halogen Interactions.

We have added the {Re X } (X=Br, Cl) synthon to a pocket-based ligand to provide supramolecular design using halogen⋅⋅⋅halogen interactions within an Fe system that has the potential to undergo spin crossover (SCO). By removing the solvent from the crystal lattice, we "switch on" halogen⋅⋅⋅halogen interactions between neighboring molecules, providing a supramolecular cooperative pathway for SCO. Furthermore, changes to the halogen-based interaction allow us to modify the temperature and nature of the SCO event.

Tetranuclear oxido-bridged thorium(iv) clusters obtained using tridentate Schiff bases.

Thorium(iv) complexes are currently attracting intense attention from inorganic chemists due to the development of liquid-fluoride thorium reactors and the fact that thorium(iv) is often used as a model system for the study of the more radioactive Np(iv) and Pu(iv). Schiff-base complexes of tetravalent actinides are useful for the development of new separation strategies in nuclear fuel processing and nuclear waste management. Thorium(iv)-Schiff base complexes find applications in the colorimetric detection of this toxic metal ion and the construction of fluorescent on/off sensors for Th(iv) exploiting the ligand-based light emission of its complexes.

Multifunctionality in Two Families of Dinuclear Lanthanide(III) Complexes with a Tridentate Schiff-Base Ligand.

The employment of -(2-carboxyphenyl)salicylideneimine in 4f metal chemistry has led to two families of dinuclear complexes depending on the lanthanide(III) used. Representative members exhibit interesting magnetic, optical, and catalytic properties.

A potent, selective, and orally bioavailable inhibitor of the protein-tyrosine phosphatase PTP1B improves insulin and leptin signaling in animal models.

The protein-tyrosine phosphatase PTP1B is a negative regulator of insulin and leptin signaling and a highly validated therapeutic target for diabetes and obesity. Conventional approaches to drug development have produced potent and specific PTP1B inhibitors, but these inhibitors lack oral bioavailability, which limits their potential for drug development. Here, we report that DPM-1001, an analog of the specific PTP1B inhibitor trodusquemine (MSI-1436), is a potent, specific, and orally bioavailable inhibitor of PTP1B.

Connectivity and Topology Invariance in Self-Assembled and Halogen-Bonded Anionic (6,3)-Networks.

We report here that the halogen bond driven self-assembly of 1,3,5-trifluorotriiodobenzene with tetraethylammonium and -phosphonium bromides affords 1:1 co-crystals, wherein the mutual induced fit of the triiodobenzene derivative and the bromide anions (halogen bond donor and acceptors, respectively) elicits the potential of these two tectons to function as tritopic modules (6,3). Supramolecular anionic networks are present in the two co-crystals wherein the donor and the acceptor alternate at the vertexes of the hexagonal frames and cations are accommodated in the potential empty space encircled by the frames. The change of one component in a self-assembled multi-component co-crystal often results in a change in its supramolecular connectivity and topology.

Dinuclear lanthanide(III)/zinc(II) complexes with methyl 2-pyridyl ketone oxime.

The first use of methyl 2-pyridyl ketone oxime (mpkoH) in zinc(II)/lanthanide(III) chemistry leads to the [ZnLn(mpko)3(mpkoH)3](ClO4)2 and [ZnLn(NO3)2(mpko)3(mpkoH)] families of dinuclear Zn(II)Ln(III) complexes displaying blue-green, ligand-based photoluminescence; the Zn(II)Dy(III) compound shows field-induced relaxation of magnetization.

Zn(II)/pyridyloxime complexes as potential reactivators of OP-inhibited acetylcholinesterase: in vitro and docking simulation studies.

In order to investigate the ability of metal complexes to act as reactivators of organophosphorus compounds (OP)-inhibited acetylcholinesterase (AChE), we have synthesized and crystallographically characterized three novel mononuclear Zn(II) complexes formulated as [ZnCl2{(4-py)CHNOH}2] (1), [ZnBr2{(4-py)CHNOH}2] (2) and [Zn(O2CMe)2{(4-py)CHNOH}2]∙2MeCN (3∙2MeCN), where (4-py)CHNOH is 4-pyridinealdoxime. Their reactivation potency was tested in vitro with a slight modification of the Ellman's method using Electric eel acetylcholinesterase and the insecticide paraoxon (diethyl 4-nitrophenyl phosphate) as inhibitor. The activity of the already reported complex [Zn2(O2CPh)2{(4-py)CHNOH}2]·2MeCN (4·2MeCN) and of the clinically used drug obidoxime 1,1'-[oxybis(methylene)]bis{4-[(E)- (hydroxyimino)methyl]pyridinium} was also examined.

Investigation of the zinc(II)-benzoate-2-pyridinealdoxime reaction system.

The employment of pyridine-2-carbaldehyde oxime (paoH) in zinc(II) benzoate chemistry, in the absence or presence of azide ions, is described. The syntheses, crystal structures and spectroscopic characterization are reported for the complexes [Zn(O(2)CPh)(2)(paoH)(2)] (1), [Zn(12)(OH)(4)(O(2)CPh)(16)(pao)(4)] (2) and [Zn(4)(OH)(2)(pao)(4)(N(3))(2)] (3). The Zn(II) centre in octahedral 1 is coordinated by two monodentate PhCO(2)(-) groups and two N,N'-chelating paoH ligands.

Metal ion-assisted transformations of 2-pyridinealdoxime and hexafluorophosphate.

Metal-ion mediated reactions of 2-pyridinealdoxime and hexafluorophosphate lead to Zn(II) complexes containing picolinic acid, picolinamide and monofluorophosphate (-2) as ligands.

Synthesis, Crystal Structures, and DNA Binding Properties of Zinc(II) Complexes with 3-Pyridine Aldoxime.

The employment of 3-pyridine aldoxime, (3-py)CHNOH, in Zn(II) chemistry has afforded two novel compounds: [Zn(acac)(2){(3-py)CHNOH}]·H(2)O (1·H(2)O) [where acac(-) is the pentane-2,4-dionato(-1) ion] and [Zn(2)(O(2)CMe)(4){(3-py)CHNOH}(2)] (2). Complex 1·H(2)O crystallizes in the monoclinic space group P2(1)/n. The Zn(II) ion is five-coordinated, surrounded by four oxygen atoms of two acac(-) moieties and by the pyridyl nitrogen atom of the (3-py)CHNOH ligand.

Synthesis, X-Ray Structure, and Characterization of Catena-bis(benzoate)bis{N,N-bis(2-hydroxyethyl)glycinate}cadmium(II).

The reaction of N, N-bis(2-hydroxyethyl)glycine (bicine; bicH(3)) with Cd(O(2)CPh)(2) · 2H(2)O in MeOH yielded the polymeric compound [Cd(2)(O(2)CPh)(2)(bicH(2))(2)](n)(1). The complex crystallizes in the tetragonal space group P4(1)2(1)2. The lattice constants are a = b = 12.

Use of the 2-Pyridinealdoxime/N,N'-Donor Ligand Combination in Cobalt(III) Chemistry: Synthesis and Characterization of Two Cationic Mononuclear Cobalt(III) Complexes.

The use of 2-pyridinealdoxime (paoH)/N,N'-donor ligand (L-L) "blend" in cobalt chemistry has afforded two cationic mononuclear cobalt(III) complexes of the general type [Co(pao)(2)(L-L)](+), where L-L = 1,10-phenanthroline (phen) and 2,2'-bipyridine (bpy). The CoCl(2)/paoH/L-L (1 : 2 : 1) reaction system in MeOH gives complexes [Co(III)(pao)(2)(phen)]Cl.2H(2)O (1.

A tetrahedron in a cube: a dodecanuclear Zn(II) benzoate cluster from the use of 2-pyridinealdoxime.

The reactions of 2-pyridinealdoxime with Zn(O(2)CPh)(2)·2H(2)O have led to a mononuclear complex and a dodecanuclear cluster; the Zn(12) compound, whose metallic skeleton describes a tetrahedron encapsulated in a distorted cube, is the biggest Zn(II) oxime cluster discovered to date and displays photoluminescence with a maximum at 354 nm upon maximum excitation at 314 nm.

Wheel-like Mn(II)6 and Ni(II)6 complexes from the use of 2-pyridinealdoxime and carboxylates.

The employment of 2-pyridinealdoxime, (py)C(H)NOH, in nickel(II) and manganese(II) carboxylate chemistry under solvothermal conditions is reported. The syntheses, crystal structures and magnetochemical characterization (for two representative compounds) are described for [Ni(6)(O(2)CMe)(6){(py)C(H)NO}(6)].H(2)O (1.