L. I. Myachina

Co(III) complexes with optically active bis(menthane), pinano-para-menthane, carano-para-menthane, and bis(carane) propylenediaminodioximes

Novel optical ligands bis(menthane) (H2L1), pinano-para-menthane (H2L2), and carano-para-menthane (H2L3) propylenediaminodioximes are obtained. Diamagentic Co(III) complexes of the composition Co(HL1)Cl2 (I), Co(HL2)Cl2 (II), Co(HL3)Cl2 (III), and Co(HL4)Cl2 · H2O(IV) are synthesized by reactions of CoCl2 with H2L1, H2L2, H2L3 and bis(carane) propylenediaminodioxime (H2L4) in ethanol in air. The crystal and molecular structures of compound I is determined by X-ray diffraction analysis. The crystals are monoclinic with the unit cell parameters a = 7.8385(3) Å, b = 11.4074(6) Å, c = 14.9509(6) Å, β = 104.278(2)°, V = 1295.57(10) Å3, Z = 2, ρ(calcd) = 1.367 g/cm3, F(000) = 564, M = 533.41, space group P21. The crystal structure of complex I consists of individual mononuclear molecules. The Co3+ ion coordinates four N atoms of tetradentate cycle-forming anionic ligand and two Cl atoms. The coordination polyhedron of Cl2N4 is a distorted octahedron. The 13C and 1H NMR spectra of the complexes synthesized confirm coordination of four N atoms of a ligand.

Binuclear Pd(II) complexes with chiral ethylenediaminodioxime (H2L) and bis-α-thiooxime (H2L1), the derivative of monoterpenoid(+)-3-carene. Crystal structures of [Pd2(H2L)Cl4] and [Pd2(H2L1)Cl4] · 3CDCl3

Diamagnetic Pd(II) complexes with the chiral ethylenediaminodioxime (H 2 L) and bis-α-thiooxime (H2L1), the derivatives of monoterpenoid (+)-3-carene, of the composition Pd2(H2L)Cl4(I), Pd2(H2L1)Cl4 (II), and the solvate Pd2(H2L1)Cl4·3DCl3 (III) were synthesized. The crystal structures of complex I and solvate III were determined from X-ray diffraction data. The structures consist of acentric binuclear molecules with the coordination cores PdN2Cl2 (in I) and PdNSCl2 (in III) in the form of the distorted squares. In complex I, each Pd atom coordinates two N atoms of the tetradentate bridge-cyclic ligand H2L and two Cl atoms; in compound III, one N and one S atom of the tetradentate bridge-cyclic ligand H2L1, and 2 Cl atoms. The CDCl3 molecules in compound III lie in the cavities formed by the molecules of complex II. In both structures, the PdCl2 fragments are in the trans-positions. The 1H NMR spectra indicate that the structures of complexes I, II in solutions are similar to the structures of compounds I, III in the solid state.

Synthesis of binuclear complexes of PdCl2 with chiral α,α′-diamino-meta-xylene dioximes H2L1, H2L2, and H2L3, the derivatives of the terpenes (+)-3-carene, (R)-(+)-limonene, and (S)-(−)-α-pinene. Crystal structure of [Pd2(H2L1)Cl4]

Chiral α,α′-diamino-meta-xylene dioximes H2L1, H2L2, and H2L3 were obtained from the naturally occurring terpenoids (+)-3-carene, (R)-(+)-limonene, and (S)-(−)-α-pinene, respectively. Reactions of these ligands with PdCl2 gave the diamagnetic complexes Pd2(H2L1)Cl4 (I), Pd2(H2L2)Cl4 (II), and Pd2(H2L3)Cl4 (III). According to X-ray diffraction data, the crystal structure of complex I consists of acentric binuclear molecules [Pd2(H2L1)Cl4]. The coordination polyhedron PdN2Cl2 is a square distorted in a tetrahedral manner (trapezium) made up of two N atoms of the tetradentate bridging cyclic ligand H2L1 and two Cl atoms. The fragments PdCl2 in the complex are cis to each other. According to the 1H NMR spectra of complexes I–III in CDCl3, the organic ligands are coordinated through the N atoms; in solution, the complexes exist in several forms.

Syntheses and structures of p-HOOCC6F4COOH · H2O (H2L · H2O) and luminescent coordination polymers [Tb2(H2O)4(L)3 · 2H2O]n and Tb2(Phen)2(L)3 · 2H2O

Compounds p-HOOCC6F4COOH · H2O (H2L · H2O), [Tb2(H2O)4(L)3 · 2H2O]n (I), and Tb2(Phen)2(L)3 · 2H2O (II) are synthesized. According to the X-ray structure analysis data, the crystal structure of H2L · H2O is built of centrosymmetric molecules H2L and molecules of water of crystallization. The crystal structure of compound I is built of layers of coordination 2D polymer [Tb2(H2O)4(L)3]n and molecules of water of crystallization. The ligands are the L2− anions performing both the tetradentate bridging and pentadentate bridging-chelating functions. The coordination polyhedron TbO9 is a distorted three-capped trigonal prism. Acid H2L manifests photoluminescence in the UV region (λmax = 368 nm). Compounds I and II have the green luminescence characteristic of the Tb3+ ions, and the band with λmax = 545 nm (transition 5D4→ 7F5) is maximum in intensity. The photoluminescence intensity of compound II is higher than that for compound I.

Cu(II) Complexes with Optically Active α-Alkylamino Oximes of Caryophyllene Type: Synthesis, Structure, and Properties

Paramagnetic complexes Cu(HL1)Cl2 (I), Cu(HL2)Cl2 · 2H2O (II), and Cu(HL1)Br2 (III) are synthesized by the reaction of copper(II) halides with the optically active α-alkylamino oximes HL1 and HL2 of caryophyllene type. Crystal and molecular structures of complex I are determined. The crystals are orthorhombic: a = 9.038(2) Å, b = 11.990(2) Å, c = 11.990(2) Å, V = 2004.8(7) Å3, space group P212121, Z = 4, ρ(calcd) = 1.812 g/cm3, R1 = 0.0632. In a mononuclear complex I, the coordination polyhedron of CuCl2N2 is a distorted square. The structures of complexes II and III are suggested on the basis of EPR, IR and Raman spectroscopy data.

Synthesis of solvates of the copper(II) complex with chiral caryophyllane-type morpholino oxime (HL). Structure of Cu(HL)Cl2 · CHCl3

Paramagnetic Cu(HL)Cl2 · 0.25CHCl3 (I) and Cu(HL)C12 · 0.25CH2C12 (II), where HL is the optically active morpholino oxime obtained from the terpenoid caryophyllene, were synthesized. The crystals of Cu(HL)Cl2 · CHCl3 (III) were isolated. According to X-ray diffraction data, the crystals of III are composed of acentric mononuclear complex molecules Cu(HL)Cl2 and solvate molecules CHCl3. In the complex molecules, the Cu ion coordinates two N atoms of the bidentate chelating ligand HL and two C1 atoms at the vertices of a distorted tetrahedron. The translationally identical molecules of the complex combined by H-bonds form chains along the axis x.

Preparation of photoluminescent compounds of Eu(III), Sm(III), and Dy(III) containing anions of tetrafluoroterephthalic acid

The Ln2(H2O)4(L)3·2H2O and Ln2(phen)2(L)3·2H2O complexes [Ln = Eu(III), Sm(III), or Dy(III); H2L = C6F4(COOH)2, phen = 1,10-phenanthroline] have been prepared. Structures of the prepared compounds have been confirmed by X-ray diffraction and IR spectroscopy studies. The complexes of Eu(III) have exhibited red photoluminescence stronger than that of the complexes of Sm(III) and Dy(III).

Synthesis and structure of optically active compounds [Ni(HL1)]NO3 and [Ni(HL2)]NO3H2O containing anions of diaminodioximes H2L1 and H2L2 derived from α-Pinene and (+)-3-Carene as Ligands

New optically active levorotatory compounds [Ni(HL1)]NO3 (I) and [Ni(HL2)]NO3· H2O (II) containing the anions of chiral diaminodioximes, H2L1 and H2L2, derived from the terpenes ±-pinene and (+)-3- carene, respectively, were synthesized. Complexes I and II were studied by X-ray diffraction. The crystal structures of compounds are ionic, being composed of the [Ni(HL1)]+ or [Ni(HL2)]+ cations and the outer-sphere NO−3 anions. The Ni2+ ion coordinates four N atoms of the tetradentate chelating ligand, the NiN4 coordination unit being shaped like a tetrahedrally distorted square. Compounds I and II are diamagnetic, which corresponds to a low-spin d8 configuration. The NMR spectra of compounds were recorded and analyzed.

Nickel(II) Complex with Optically Active (3S)-3-Hydroxyaminocaran-4-one E-oxime and Its Oxidation into a Complex with Nitroxyl Radicals

Ni(II) chelate with (3S)-3-hydroxyaminocaran-4-one E-oxime (H2L) of composition Ni(HL)2 · 2H2O was synthesized. The compound is diamagnetic, which suggests the square-planar structure of a NiN4 coordination unit. The electronic absorption spectroscopy and EPR methods were used to study its oxidative dehydrogenation in benzene resulting in a compound containing nitroxyl radicals Ni(HL·)2 and exhibiting strong antiferromagnetic exchange coupling of unpaired electrons of the radicals. An intermediate paramagnetic form Ni(HL)(HL·) was discovered by the EPR method.

Synthesis of Octafluorobiphenyl-4,4′-dicarboxylic acid and photoluminescent compounds based thereon

Octafluorobiphenyl-4,4′-dicarboxylic acid (H2L) and its complexes with Tb(III) and Eu(III) [Ln2(H2O)4(L)3·3H2O and Ln2(phen)2(L)3·2H2O] have been prepared; their structure has been elucidated from IR spectroscopy and X-ray diffraction analysis data. Thermal properties of the compounds have been studied. The complexes of Tb(III) and Eu(III) exhibit green and red photoluminescence, respectively.