Trigonal dodecahedral sodium coordination in a trinuclear copper(II)-sodium complex incorporating a salen-type compartmental Schiff base

A new trinuclear heterometallic complex, [(CuL)Na(CuL)]·ClO4 (1), has been prepared using a Schiff base, H2L (where H2L=N,N′-(1,2-phenylene)-bis(3-methoxysalicylideneimine) and characterized by elemental analysis, Fourier transform infra-red (FT-IR) spectroscopy, UV/Vis, magnetic, electrochemical, and single crystal X-ray diffraction methods. The structure analysis reveals that two metallo-ligand [(CuL)] units are connected to each other by a sodium ion resulting in the cationic unit [(CuL)Na(CuL)]+. Both the copper(II) ions display an almost square planar geometry while the sodium ion adopts a trigonal-dodecahedral coordination geometry. The spectroscopic and other physicochemical studies are in good agreement with the crystal structure of the complex

Synthesis of 1,1′-(2,6-dihydroxy-2,6-dimethyl-3,7-dioxabicyclo [3.3.1]nonane-1,5-diyl)diethanone dihydrate: crystal structure and quantitative analysis of molecular interaction <i>via</i> molecular electrostatic potential and Hirshfeld surface analysis

<p>A new bicyclononane derivative, 1,1′-(2,6-dihydroxy-2,6-dimethyl-3,7-dioxa-bicyclo[3.3.1]nonane-1,5-diyl) diethanone dihydrate (<b>1</b>), has been synthesized and structurally characterized by the single-crystal X-ray diffraction technique. In the solid-state structure of the compound, molecular units are interlinked <i>via</i> strong hydrogen bonds as well as non-classical weak hydrogen bonds leading to a three-dimensional supramolecular architecture. Solid-state DFT optimized geometry in (<b>1</b>) agrees closely with that obtained from the crystallographic analysis. The C(dioxa-bicyclononane)–H … O(hydroxy) hydrogen bond generates cyclic <math><msubsup>R<mn>2</mn><mn>2</mn></msubsup></math> (10) ring in (<b>1</b>) which are further connected through C–H … O and O–H … O hydrogen bonds into a three-dimensional framework in the title compound. Hirshfeld surface analysis of the title compound along with some related nonane derivatives retrieved from the Cambridge Structural Database shows that the most of the Hirshfeld surface area in this class of compounds is due to H … H and O … H interactions.</p

Syntheses, characterization, and crystal structures of few dioxomolybdenum(VI) complexes incorporating tridentate hydrazones

Three new cis-dioxomolybdenum(VI) complexes, [MoO 2 (L 1 )(CH 3 OH)] (1), [MoO 2 (L 2 )(CH 3 OH)] (2), and [MoO 2 (L 3 )(CH 3 OH)] (3) have been synthesized using three different tridentate hydrazone Schiff bases, (E)-N 0 -(4-oxopentan-2-ylidene)isonicotinohydrazide (H 2 L 1 ), (E)-N 0 -(4-oxo-4-phenylbutan-2- ylidene)isonicotinohydrazide) (H 2 L 2 ), and (E)-N 0 -(2,3-dihydroxybenzylidene)benzohydrazide (H 2 L 3 ), respectively. The ligands and their metal complexes were characterized by different physicochemical techniques. The molecular structures of the complexes were conclusively established by single crystal X-ray diffraction which reveals that six coordinated molybdenum(VI) atom adopts distorted octahedral geometry. The tridentate hydrazone coordinates to the metal centers in their di-anionic form. The crystal packing of the complexes also reveals that classical hydrogen bonding between adjacent units result in stair-like 1D structure for 1 while an interlocked dimer for 2 and 3, respectively. Crystal packing also reveals that further non-classical interactions lead to 2D (for 1 and 3) and 3D (for 2) supramolecular structures in their solid state. Hirshfeld surface analyses were carried out to get insight to the intermo- lecular interactions. Thermal stabilities and electrochemical behavior of the complexes have also been investigated

Synthesis, Characterization and Magnetic Studies of a Tetranuclear Manganese(II/IV) Compound Incorporating an Amino-Alcohol Derived Schiff Base

A new tetranuclear mixed-valence manganese(II/IV) compound [MnIIMnIV3(&#956;-Cl)3(&#181;3-O)(L)3] (1) (where H3L = (3E)-3-((Z)-4-hydroxy-4-phenylbut-3-en-2-ylideneamino)propane-1,2-diol) has been synthesized and characterized by different physicochemical methods. Single crystal X-ray diffraction analysis reveals that 1 is a tetrahedral cluster consisting of a Mn4Cl3O4 core in which the only Mn(II) ion is joined through three &#956;2-O bridges to an equilateral triangle of Mn(IV) ions, which are connected by a &#956;3-O and three &#956;2-Cl bridges. The redox behavior of 1 was studied by cyclic voltammetry. Variable temperature magnetic susceptibility measurements of 1 revealed predominant antiferromagnetic coupling inside the Mn4Cl3O4 cluster

Syntheses, structural variations and fluorescence studies of two dinuclear zinc(II) complexes of a Schiff base ligand with an extended carboxylate side arm

A potentially tetradentate Schiff base ligand containing carboxylic acid group, HL, (E)-2-((pyridin-2-yl) methyleneamino)-5-chlorobenzoic acid is synthesized and characterized. Reaction of HL with hydrated zinc(II) trichloroacetate and zinc(II) trifluoroacetate under similar reaction condition yields two discrete dinuclear complexes, [Zn(L)(Cl)] 2 (1) and [Zn(L)(CF 3 COO)] 2 (2) and characterized by different physico- chemical methods. Single crystal X-ray structural characterization reveals different ligating properties of the coordinated anionic ligand (L ? ) in its zinc(II) complexes. The side arm carboxylate of L ? shows m 1,3 - carboxylato-bridging mode in 1 and connects zinc(II) atoms in syn-anti fashion while it exhibits a m 1,1 - carboxylato-bridging mode in 2. The metal ions display distorted square pyramidal geometries in both the structures and associated with different degrees of distortions. The fluorescence spectra of HL and its zinc(II) complexes recorded in methanol at room temperature which reveal the enhancement of emis- sion intensity for the complexes compared to that of the free ligand. Thermogravimetric analyses (TGA) reveal high thermal stabilities of the complexes

Azide/thiocyanate incorporated cobalt(III)-Schiff base complexes: Characterizations and catalytic activity in aerobic epoxidation of olefins

Reaction of cobalt(II) perchlorate hexahydrate with a potentially tetradentate Schiff base ligand, HL (2-methoxy-6-(2-diethylaminoethylimino)methyl]phenol) in presence of sodium azide and sodium thiocyanate yields two complexes Co( L)( HL)(N-3)]center dot ClO4 ( 1) and Co( L)( HL)(NCS)] center dot ClO4 ( 2); both being characterized by different physicochemical methods. Crystal structure of 1 was determined by single crystal X-ray diffraction while that of 2 was reported earlier. In 1, the central cobalt(III) adopts slightly distorted octahedral geometry with same donor set to that of 2. Catalytic efficacy of the complexes towards epoxidation of different alkenes under aerobic condition were investigated in homogeneous medium which reveals that 1 is better catalyst than 2 with respect to alkene oxidation, reflected from the turn over frequencies (TOF) measured at an optimum temperature of 60 degrees C in acetonitrile. (C) 2014 Published by Elsevier B.V

A novel centrosymmetric dinuclear cadmium(II) Schiff base complex with unusual bridging carboxylate: Synthesis, crystal structure and luminescence properties

International audienceA novel centrosymmetric dinuclear Cd(II) complex [CdL (CH3COO)]2 (1) has been synthesized by the reaction of Cd(CH3COO)2·2H2O with a Schiff base ligand HL [HL = (E)-2-((pyridin-2-yl)methyleneamino)benzoic acid]. Title complex has been systematically characterized by elemental analysis, FT-IR, and thermal studies. Single crystal X-ray structural analysis reveals that Cd(II) centers in 1 adopt distorted monocapped octahedral geometry and held together by rare doubly μ-2, 2 carboxylato bridging which is believed to be first relating to anthranilic carboxylate. At room temperature, compound in the solid state exhibits moderate photoluminescence activities indicating its potential as promising photoactive material

A novel mixed ligand coordination polymer of copper(II): Synthesis, characterisation and magneto-structural correlation

A novel 1D coordination chain polymer {[Cu2(pydc)2(1,10-phen)(H2O)2]·3H2O}n (pydc = pyridine-2,3-dicarboxylate, 1,10-phen = 1,10-phenantroline) has been synthesised and characterised by elemental analysis, FT-IR spectrum, thermal analysis and variable temperature magnetic susceptibility studies. Single crystal X-ray diffraction measurement of the complex shows two Cu(II) centres are in distorted square pyramidal geometry. The complex shows very interesting hydrogen bonding modes involving the lattice and coordinated water molecules with dicarboxylates. Low temperature magnetic susceptibility studies reveal a weak antiferromagnetic coupling interaction of J = − 5.71 cm−1