Synthesis,crystal structures,and catalytic property of dioxomolybdenum(VI) complexes with hydrazone ligands derived from 3,5-Di-<Emphasis Type="Italic">tert</Emphasis>-butylsalicylaldehyde

Two new dioxomolybdenum(VI) complexes, [MoO₂L¹(MeOH)] (I) and [MoO₂L²] (II), where L¹ and L² are the anionic forms of N'-(2-hydroxy-3,5-di-tert-butylbenzylidene)-4-methoxybenzohydrazide and 2-amino-N'-(2-hydroxy-3,5-di-tert-butylbenzylidene)benzohydrazide, respectively, have been synthesized and characterized by elemental analysis, FT-IR spectra, and single crystal X-ray determination (CF files CCDC nos. 1448089 (I), 1487063 (II)). The crystal of I is monoclinic: space group P21/n, a = 7.353(1), b = 24.758(3), c = 13.891(2) Å, β = 101.013(2)°, V = 2482.3(6) Å3, Z = 4, R ₁ = 0.0848, wR ₂ = 0.2050. The crystal of II is monoclinic: space group P2₁/c, a = 6.752(1), b = 16.947(1), c = 19.510(1) Å, β = 96.891(2)°, V = 2216.5(4) Å3, Z = 4, R ₁ = 0.0670, wR ₂ = 0.1638. The Mo atom in complex I is in octahedral coordination, with three donor atoms of the hydrazone ligand, two oxo groups, and one methanol O atom. The Mo atom in complex II is in square pyramidal coordination, with three donor atoms of the hydrazone ligand, and two oxo groups. The complexes have interesting catalytic properties for sulfoxidation reactions.     

Syntheses,characterization, and crystal structures of two dinuclear nickel(II) and copper(II) complexes with Schiff bases

The phenolic azide bridged dinuclear nickel(II) complex, [Ni₂(L¹)₂(N₃)(H₂O)(μ_1,1-N₃)] · EtOH (I), and the thiocyanate bridged dinuclear copper(II) complex, [Cu₂(L²)₂(μ_1,1-NCS)₂] (II), where L¹ and L² are the deprotonated forms of 2-mothoxy-6-[(2-piperidin-1-ylethylimino)methyl]phenol and 2,4-dichloro-6-[(2-methylaminoethylimino)methyl]phenol, respectively, were synthesized and characterized by elemental analysis, IR spectra, and single-crystal X-ray diffraction. The crystal of I is orthorhombic: space group Pbca, a = 12.172(1), b = 20.953(1), c = 29.779(2) Å, V = 7594.8(9) ų, Z = 8. The crystal of II is monoclinic: space group P2₁/n, a = 8.7615(11), b = 19.672(2), c = 16.568(2) Å, β = 99.449(2)°, V = 2816.9(6) ų, Z = 4. The Ni atoms in I are in octahedral coordinations, and the Cu atoms in II are in square-pyramidal coordinations.     

Synthesis,crystal structures,and antibacterial activities of Schiff base nickel(II) and cadmium(II) complexes with tridentate Schiff bases

Reaction of tridentate Schiff bases with nickel and cadmium salts in methanol afforded two new mononuclear complexes, [Ni(L¹)₂] (I) and [Cd(L²)₂] (II), where L¹ and L² are the anions of 2-bromo-4-chloro-6-[(3-dimethylaminopropylimino)methyl]phenol (HL¹) and 2-bromo-4-chloro-6-[(3-morpholin-4-ylpropylimino)methyl]phenol (HL²), respectively. The complexes were characterized by singlecrystal X-ray diffraction (CIF files CCDC nos. 1428653 (I) and 1428654 for (II)), FT-IR, and elemental analysis. Complex I crystallizes in the monoclinic space group P2 ₁/c, with a = 8.8216(8), b = 14.0424(8), c = 11.8687(12) Å, β = 111.238(2)°, V = 1370.4(2) ų, Z = 2. Complex II crystallizes in the monoclinic space group P2 ₁/n, with a = 9.6774(4), b = 15.8970(6), c = 20.3144(7) Å, β = 90.408(2)°, V = 3125.1(2) ų, Z = 4. The metal atoms in the complexes are coordinated by two tridentate Schiff base ligands, forming octahedral coordination. The free Schiff bases and the complexes were assayed for antibacterial activities. Both complexes are more active against the bacteria than the free Schiff bases. Complex II has the MIC value of 0.39 μg mL^–1 against Bacillus subtilis.     

Synthesis,crystal structure,and antibacterial activity of oxovanadium(V) complexes derived from <Emphasis Type="Italic">N</Emphasis>'-[1-(5-fluoro-2-hydroxyphenyl)methylidene]nicotinohydrazide and <Emphasis Type="Italic">N</Emphasis>'-(5-fluoro-2-hydroxybenzylidene)-2-hydroxynaphthylhydrazide

Two new oxovanadium(V) complexes, [VOL¹(OCH₃)(CH₃OH)] (I) and [VOL²(OCH₃)] (II), where L¹ and L² are the di-anionic form of N'-[1-(5-fluoro-2-hydroxyphenyl)methylidene]nicotinohydrazide and N'-(5-fluoro-2-hydroxybenzylidene)-2-hydroxynaphthylhydrazide, respectively, have been synthesized and characterized by elemental analysis, FT-IR spectra, and single crystal X-ray determination (CIF files CCDC nos. 891852 (I), 891853 (II)). The crystal of I is monoclinic: space group P2₁/c, a = 8.061(1), b = 15.293(2), c = 13.471(2) Å, ß = 92.595(2)°, V = 1658.8(4) ų, Z = 4. The crystal of II is monoclinic: space group P2₁/n, a = 7.4454(9), b = 8.0833(9), c = 28.906(2) Å, ß = 92.644(2)°, V = 1737.8(3) ų, Z = 4. The V atom in I is in an octahedral coordination, and that in II is in a square-pyramidal coordination. The antibacterial activity of the compounds against various bacteria was assayed.     

Synthesis,crystal structure,and luminescent properties of silver complexes with 2-methylquinoline

The complexes [AgL₂(NO₃)] (I) and [AgL₂(CH₃SO₃)] · H₂O (II) (L is 2-methylquinoline, C₁₀H₉N) have been synthesized and structurally characterized by single-crystal X-ray diffraction. Crystals of I are monoclinic, space group P2₁/n, a = 9.296(1) Å, b = 13.495(1) Å, c = 14.931(1) Å, β = 95.06(1)°, V = 1865.8(3) ų, ρ_calc = 1.624 g/cm³, Z = 4. Crystals of II are monoclinic, space group P2₁/n, a = 13.147(1) Å, b = 11.767(1) Å, c = 13.814(1) Å, β = 96.06(1)°, V = 2124.3(3) ų, ρ_calc = 1.599 g/cm³, Z = 4. Compounds I and II are composed of discrete complexes of similar structure but with different orientation of the methyl groups of ligand L (trans and cis arrangement, respectively). Both anions, NO ₃ ^- and CH₃SO ₃ ^- function as a chelating weakly bound ligand for the Ag⁺ ion. The presence of water molecules in II is favorable for the formation of dimeric supramolecular moieties between the centrosymmetrically arranged Ag⁺ complexes with 2-methylquinoline. The luminescence spectra of solid complexes I and II showed a bathochromic shift as compared to the spectrum of L in acetonitrile. Complexes I and II have been characterized by ¹H and ¹³C{H} NMR spectra in CD₃CN.     

Synthesis and structure of diethylenetriammonium tetrachloroaurates(III)

The (DienH₃)[AuCl₄]₃ · H₂O (I) and (DienH₃)₂[AuCl₄]Cl₅ (II) compounds were obtained by the reaction of HAuCl₄ with diethylenetriamine trihydrochloride (DienH₃Cl₃) in hydrochloric acid. The compounds were characterized by elemental analysis, X-ray diffraction, thermogravimetry, and IR spectroscopy. Crystals of I and II are monoclinic with space group P2₁/n. For I, a = 12.2314(3) Å, b = 14.6077(5) Å, c = 13.2680(5) Å, β = 106.7350(10)°, V = 2270.22(13) ų, Z = 8. For II, a = 6.62990(10) Å, b = 17.9026(5) Å, c = 10.3661(3) Å, β = 101.9230(10)°, V = 1203.83(5) ų, Z = 2. Both structures are ionic. The gold atoms in I and II have a 4 + 2 coordination environment. The Au-Cl bond lengths are within 2.276–2.294 Å, and the axial Au…Cl contacts are within 3.315–3.405 Å. The diethylenetriammonium cation in I and II has different conformations.     

Syntheses,characterization, crystal structures and fluorescence property of Zinc(II) complexes with Schiff bases

Two new mononuclear Schiff base zinc(II) complexes, [ZnCl₂(L¹)] ? MeOH (I) and [Zn(L²)₂] (II) (L¹ = 2-bromo-4-chloro-6-[(2-ethylammonioethylimino)methyl]phenolate; L² = 2-bromo-4-chloro-6-(isopropyliminomethyl)phenolate), have been prepared and characterized by elemental analyses, infrared and UV-Vis spectroscopy, and single-cyrstal X-ray diffraction (CIF files CCDC nos. 1408962 (I), 1408961 (II)). Complex I crystallizes in the triclinic space group \(P\overline 1\) with unit cell dimensions a = 9.859(1), b = 13.015(2), c = 19.817(3) Å, α = 73.591(2)°, β = 76.032(2)°, γ = 82.966(2)°, V = 2363.0(5) ų, Z = 4, R ₁ = 0.0925, and wR ₂ = 0.2257. Complex II crystallizes in the monoclinic space group P2₁/c with unit cell dimensions a = 7.6387(7), b = 22.307(2), c = 21.443(2) Å, β = 96.216(3)°, V = 3632.4(6) ų, Z = 8, R ₁ = 0.0651, and wR ₂ = 0.1100. The both Zn atoms in I is four-coordinated in a tetrahedral geometry by the NO donor set of the Schiff base ligand, and two Cl ligands. The Zn atom in II is in a tetrahedral geometry by two N and two O atoms from two Schiff base ligands. Crystals of the complexes are stabilized by hydrogen bonds and weak π…π interactions. Fluorescence property of the complexes have been determined.     

Synthesis and crystal structures of cobalt(III) and zinc(II) complexes with Schiff bases

Two new cobalt(III) and zinc(II) complexes, [Co(L¹)₂ (H₂O)] · ClO₄ (I) and [Ni(L²)₂ (H₂O)₂] · 2ClO₄ (II), where L¹ is the deprotonated form of 5-methoxy-2-[(2-morpholin-4-ylethylimino)methyl]phenol, and L² is the zwitterionic form of 2-[(2-isopropylaminoethylimino)methyl]-5-methoxyphenol, were synthesized and structurally characterized by elemental analyses, IR spectra, and single-crystal X-ray diffraction. The crystal of I is monoclinic: space group P2₁/c, a = 11.1512(4), b = 28.2424(11), c = 10.9655(4) Å, β = 95.746(2)°, V = 3436.1(2) ų, Z = 4. The crystal of II is triclinic: space group P2₁/c, a = 8.1441(2), b = 10.4531(3), c = 10.8849(3) Å, α = 84.0240(10)°, β = 76.9800(10)°, γ = 74.2280(10)°, V = 867.92(4) ų, Z = 1. Complex I consists of a mononuclear cobalt(III) complex cation and a perchlorate anion. Complex II consists of a crystallographic centrosymmetric mononuclear nickel(II) complex cation and two perchlorate anions. Each metal atom in the complexes is in an octahedral coordination.     

Crystal structure of adducts of copper(II) acetylacetonate and hexafluoroacetylacetonate with 4-aminopyridine

Single crystal X-ray diffraction is used to investigate two synthesized β-diketonate complexes of copper(II) with aminopyridine: Cu(4-NH₂Py)(aa)₂ (I) and Cu(4-NH₂Py)(hfa)₂ (II). The crystals of I and II have a monoclinic system; the unit cell parameters of I are: P2₁/n space group, a = 8.2921(3) Å, b = 14.7243(5) Å, c = 13.4970(4) Å, β = 102.426(1)°, V = 1609.32(9) ų, Z = 4; for II: C2/c space group, a = 23.5704(5) Å, b = 11.4977(2) Å, c = 16.0285(3) Å, β = 109.265(1)°, V = 4100.6(1) ų, Z = 8. The structures of I and II are molecular; they are composed of isolated molecules. The coordination polyhedron of the copper atom is formed by the O atoms of two acetylacetonate ligands (Cu-O 1.940(2)–2.171(2) I and the O atoms of two hexafluoroacetylacetonate ligands (Cu-O 1.940(2)–2.215(3) Å) in II. The molecules of 4-NH₂Py are bonded to the copper atom via the nitrogen atom of the aromatic ring (Cu-N 2.008(2) Å in I and Cu-N 1.978(3) Å in II). Noncoordinated amino groups join the molecules of the complexes together by means of N-H…O hydrogen bonds.     

Synthesis and crystal structures of binuclear complexes of cobalt(II) and cadmium(II) diisobutyldithiophosphinates with hexamethylenetetramine

Heteroligand complexes [Co₂(HMTA)(iso-Bu₂PS₂)₄] (I) (μ_eff = 4.67 μB) and [Cd₂(HMTA)(iso-Bu₂PS₂)₄] (II) have been synthesized. Single crystals of compounds I and II have been obtained. The crystals are monoclinic: a = 32.622(2) Å, b = 9.4891(6) Å, c = 21.7570(13) Å, β = 125.774(1)^o, V = 5464.3(6) Å,³, Z = 4, ρ_calcd = 1.331 g/cm³ for I; a = 34.6092(7) Å, b = 9.5595(2) Å, c = 22.3473(5) Å, β = 127.144(1)^o, V = 5893.5(2) Å, Z = 4, ρ_calcd = 1.355 g/cm³ for II; space group for both complexes C2/c. Structures I and II are based on discrete binuclear molecules. The coordination polyhedra of the Co and Cd atoms are distorted tetragonal pyramids NS₄, with the bases formed by four S atoms of two bidentate chelating ligand iso-Bu₂PS ₂ ^? and the axial vertices occupied by N atoms of bidentate bridging HMTA ligand. The character of interaction of the molecules in structures I and II is considered.     

Synthesis,Structures, and Antibacterial Activities of Two Methanol Coordinated Zinc Complexes with Tetradentate Bis-Schiff Bases

Two methanol coordinated zinc(II) complexes, [Zn(L¹)(MeOH)] (I) and [Zn(L²)(MeOH)] (II), where L¹ and L² are the dianionic form of N,N'-bis(5-fluorosalicylidene)ethane-1,2-diamine and N,N'-bis(5-fluorosalicylidene)propane-1,2-diamine, respectively, have been synthesized and characterized by physical chemical methods and single crystal X-ray diffraction (CIF files CCDC nos. 950907 (I) and 950908 (II)). Crystallographic data for I: triclinic, P \(\bar 1\), a = 8.8765(8), b = 9.6577(9), c = 10.5117(9) Å, α = 114.590(2)°, β = 91.648(3)°, γ = 97.114(3)°, V = 809.87(13) ų, Z = 2, R ₁ = 0.0307, wR ₂ = 0.0698. Crystallographic data for II: orthorhombic, Pca2₁, a = 22.946(2), b = 7.6942(7), c = 9.6234(8) Å, V = 1699.0(2) ų, Z = 4, R ₁ = 0.0320, wR ₂ = 0.0676. X-ray crystal structural study indicated that the coordination environment around each zinc(II) atom in the complexes is a five-coordinated distorted pyramid in which the apical position is occupied by a methanol oxygen atom, and the basal plane is defined by the nitrogen and oxygen donor atoms of the Schiff base ligand. The antibacterial activities of the complexes were assayed.     

Syntheses and crystal structures of hydrated complexes of strontium and barium bromides with 18-crown-6

Two complexes, namely, triaqua(18-crown-6)strontium dibromide monohydrate (I) and diaquabromo(18-crown-6)barium bromide (II), are synthesized. Their crystal structures are determined by X-ray diffraction analyses. For complex I, space group C2/c, a = 17.547 Å, b = 10.246 Å, c = 14.786 Å, β = 123.08°, Z = 4. For complex II, space group Pnma, a = 17.753 Å, b = 17.465 Å, c = 6.629 Å, Z = 4. The structures are solved by a direct method and refined by the full-matrix least-squares method in the anisotropic approximation to R = 0.056 (I) and 0.042 (II) for 2696 (I) and 2440 (II) independent reflections (CAD-4 automated diffractometer, λMoK _α radiation). Both complex cations—randomly disordered [Sr(18C6)(H₂O)₃]²⁺ in complex I and [BaBr(18C6)(H₂O)₂]⁺ in complex II—are of the host-guest type. The Sr²⁺ (Ba²⁺) cation resides in the cavity of the 18-crown-6 ligand and coordinated by all six O atoms. In the structures complexes I and II, the coordination polyhedra of the Sr²⁺ and Ba²⁺ cations (coordination number 9) can be described as distorted hexagonal bipyramids with one apex at the O atom of the water molecule in complex I or at the Br^? ligand in complex II and the other split apex at the O atoms of two water molecules.     

Synthesis and crystal structures of tetraacetylethylenediamine and <Emphasis Type="Italic">N</Emphasis>-(2-ammoniumethyl)carbamate

Two ethylenediamine derivatives—N-(2-ammoniumethyl)carbamate HN(COO^?)CH₂CH₂N⁺H₃ (I) and tetraacetylethylenediamine (H₃CC(O))₂NCH₂CH₂N(C(O)CH₃)₂ (II) (synthesized for the first time)—have been synthesized and characterized by X-ray crystallography. Compounds I and II are isolated as minor admixtures upon an attempt to synthesize ethylenediamine complexes of lanthanum and neodymium nitrates, respectively. The crystals of I and II are monoclinic: a = 7.778 Å, b = 8.060 Å, c = 7.568 Å, β = 95.73°, Z = 4, space group P2₁/c (I); a = 5.946, b = 10.255, c = 9.343 Å, β = 95.72°, Z = 2, space group P2₁/c (II). The bond lengths and bond angles lie within the corresponding standard values. Compounds I and II have different conformations of the N-C-C-N ethylenediamine moiety: gauche in I and trans in II, and the corresponding torsion angles are equal to 66.6° and 180°, respectively.     

Synthesis and crystal structures of (2.2.2-cryptand)rubidium chloride and bromide hydrates

Two complexes, (2.2.2-cryptand)rubidium chloride and bromide hydrates [Rb(Crypt-222]Hal · 3.5H₂O (Hal = Cl (I) and Br (II)), are synthesized. The structures of isomorphic crystals of compounds I and II are studied by X-ray diffraction analysis. The crystals are trigonal: space group P \(\overline 3 \), Z = 2; I: a = 11.810 Å, c = 11.302 Å; II: a = 11.890 Å, c = 11.402 Å. The structures are solved by a direct method and refined by the full-matrix least-squares method in the anisotropic approximation to R = 0.060 (I) and 0.077 (II) for 2650 (I) and 2700 (II) independent reflections (CAD-4 automated diffractometer, λMoK _α radiation). In crystals of complexes I and II, the [Rb(Crypt-222)]⁺ cation of the host-guest type lies on the crystallographic axis 3 and has the approximate symmetry D ₃. In complexes I and II, the coordination polyhedron of the Rb⁺ cation is a two-base-centered trigonal prism somewhat distorted to an antiprism. The crystals of compounds I and II contain H-bonded disordered cubes of the water molecules and Cl^? or Br^? anions.     

Synthesis,crystal structures,and antimicrobial activity of copper(II) and zinc(II) complexes derived from 2-bromo-4-chloro-6-[(2-morpholin-4-ylethylimino)methyl]phenol

An end-to-end azido-bridged dinuclear copper(II) complex [Cu₂L₂(μ_1,3-N₃)](NO₃) (I) and a mononuclear zinc(II) complex [ZnCl₂(HL)] ? CH₃OH (II), where L is 2-brom-4-chloro-6-[(2-morpholin- 4-ylethylimino)methyl]phenolate, have been prepared and characterized by elemental analyses, IR, and single crystal X-ray crystallographic determination (CIF files CCDC nos. 1415217 (I), 1415218 for (II)). The crystal of I is monoclinic: space group C2/c, a = 28.684(2), b = 7.1787(5), c = 18.292(1) Å, β = 117.887(3)°, V = 3329.1(4) ų, Z = 4. The crystal of II is monoclinic: space group P2₁/c, a = 10.8207(9), b = 12.3398(7), c = 14.9477(7) Å, β = 93.473(3)°, V = 1992.2(2) ų, Z = 4. The Schiff base ligand in I coordinates to the Cu atom through the phenolate O, imine N, and morpholine N atoms, while the Schiff base ligand in II coordinates to the Zn atom through the phenolate O and imine N atoms, with the morpholine N atom protonated. The effect of these complexes on the antimicrobial activity against Staphylococcus aureus, Escherichia coli, and Candida albicans was studied.     

Tetranuclear rhenium chalcochloride cluster complexes Cs<Subscript>3</Subscript>H[Re<Subscript>4</Subscript>Q<Subscript>4</Subscript>Cl<Subscript>12</Subscript>] · 3.33H<Subscript>2</Subscript>O (Q = Se and Te): Synthesis and structures

The tetranuclear cluster rhenium complexes Cs₃H[Re₄Q₄Cl₁₂] · 3.33H₂O (Q = Te (I) and Se (II)) with the Cl atoms as terminal ligands were obtained and structurally characterized. The structures of complexes I and II were determined by X-ray diffraction analysis. Their isostructural crystals are monoclinic; space group C2, Z = 6; a = 26.403(8) Å, b = 16.495(5) Å, c = 11.744(3) Å, β = 91.25(2)°, V = 5113(2) ų (I); a = 26.573(3) Å, b = 16.461(3) Å, c = 11.726(2) Å, β = 91.381(4)°, V = 5127.6(14) ų (II).     

Synthesis and crystal structure of zinc(II) and manganese(II) complexes of 2-(diphenylacetyl)indandione-1,3

Zinc(II) and manganese(II) complexes of 2-(diphenylacetyl)indandione-1,3 (HL) were synthesized. Crystals of [M(DMSO)₂L₂] · CHCl₃, where M= Zn^(II) (I) and Mn^(II) (II), obtained from chloroform plus dimethyl sulfoxide (DMSO) mixture were found to be isostructural based on the similarity of their unit cell parameters and unit cell volumes. The crystals are triclinic, Z = 2, space group P \(\bar 1\); a = 10.422(1) Å, b = 11.929(1) Å, c = 20.429(1) Å, α = 73.616(1)°, β = 85.095(1)°, γ = 77.586(1)° for complex I; a = 10.436(1) Å, b = 12.297(1) Å, c = 19.924(2) Å, α = 78.138(2)°, β = 87.625(2)°, γ = 82.048(2)° for complex II. X-ray structural analysis of complex I was carried out. For complex II, the structure was not refined because all of its atoms are each disordered over three to five positions. The two DMSO molecules in complex I coordinate the central metal atoms in the monodentate mode via their donor oxygen atoms to occupy an axial position and an equatorial position in an octahedral polyhedron. The other four positions are occupied by the four oxygen atoms of the two deprotonated ligands L^? coordinated in the bidentate-cyclic mode. The outer sphere of complex I contains the solvating chloroform molecule.     

Synthesis,characterization, and crystal structures of two Schiff base zinc(II) complexes with urease inhibitory activities

Two Schiff base zinc(II) complexes, [ZnBr₂L¹] · 2CH₃OH (I) (I) and [ZnBr₂L²] (II), where L¹ is 4-chloro-2-[(2-piperazin-1-ylethylimino)methyl]phenol and L² is 4-chloro-2-[(3-diethylaminopropylimino)methyl]phenol were synthesized and structurally characterized. The crystal of I is monoclinic: space group P2₁/c, a = 9.831(3), b = 18.680(6), c = 11.879(4) Å, β = 94.660(6)°, V = 2174.3(11) ų, Z = 4. The crystal of II is monoclinic: space group P2₁/n, a = 7.2310(14), b = 16.037(3), c = 15.856(3), β = 90.01(3)°, V = 1838.7(6) ų, Z = 4. The Zn atom in each complex is four-coordinated by one phenolate O and one imine N atoms of the Schiff base ligand and two bromide atoms, forming a tetrahedral coordination. The urease inhibitory activities of the complexes were evaluated.     

Synthesis,X-ray crystal structures,and antibacterial activities of Schiff base nickel(II) complexes with similar tetradentate Schiff bases

Two new mononuclear complexes, [NiL¹] · CH₃OH (I) and [NiL²] (II), have been prepared from the tetradentate Schiff bases N,N'-bis(5-methylsalicylidene)ethylenediamine (H₂L¹) and N,N'-bis(5-methylsalicylidene)- o-phenylenediamine (H₂L₂), respectively. The complexes have been characterized by physico-chemical and spectroscopic methods, as well as single-crystal X-ray determination (CIF files nos. 1428969 (I), 1428968 (II)). Complex I crystallizes in the triclinic space group P1 with a = 6.7387(14), b = 10.7010(17), c = 12.681(2) Å, α = 87.059(2)°, β = 88.828(2)°, γ = 89.901(2)°, V = 913.0(3) ų, Z = 2. Complex II crystallizes in the monoclinic space group P2₁/n with a = 12.1437(11), b = 8.0537(8), c = 18.4545(18) Å, β = 105.088(2)°, V = 1742.7(3) ų, Z = 4. The nickel atoms in the complexes are coordinated by two phenolate O and two imine N atoms of the tetradentate Schiff base ligands, forming square planar coordination. The complexes and the Schiff base compounds were assayed for antibacterial activities against three Gram-positive bacterial strains (B. subtilis, S. aureus, and St. faecalis) and three Gram-negative bacterial strains (E. coli, P. aeruginosa, and E. cloacae) by MTT method. As a result, the complexes showed effective antimicrobial activity against the microorganisms tested.     

Synthesis,crystal structures,and catalytic oxidation of olefins of dioxomolybdenum(VI) complexes with aroylhydrazone ligands

Two Mo(VI) aroylhydrazone complexes, cis-[MoO₂(L¹)(CH₃OH)] (I) and cis-[MoO₂(L²)(CH₃OH)] (II), derived from 2-bromo-N'-(3,5-dibromo-2-hydroxybenzylidene)benzohydrazide (H₂L¹) and 2-bromo-N'-(2-hydroxy-4-methoxybenzylidene)benzohydrazide (H₂L²), respectively, are reported. The complexes were characterized by elemental analyses, infrared and electronic spectroscopy, and single crystal structure analysis (CIF files CCDC nos. 1443679 (I) and 1443678 (II)). The Mo atoms are coordinated by two cis terminal oxygen, ONO from the aroylhydrazone ligand, and methanol oxygen. Complex I crystallized as monoclinic space group P2₁/_c with unit cell dimensions a = 8.075(2), b = 13.905(1), c = 16.448(1) Å, β = 91.282(2)°, V = 1846.5(4) ų, Z = 4, R ₁ = 0.0859, wR ₂ = 0.2066. Complex II crystallized as triclinic space group P \(\overline 1 \), with unit cell dimensions a = 8.0824(6), b = 10.5919(8), c = 10.7697(8), α = 96.432(2)°, β = 97.438(2)°, γ = 103.119(2)°, V = 880.8(1) ų, Z = 2, R ₁ = 0.0271, wR ₂ = 0.0571. The complexes were tested as catalyst for the oxidation of olefins and showed effective activity.