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Vol 42, No 8 (2016)
- Year: 2016
- Articles: 7
- URL: https://journals.rcsi.science/1070-3284/issue/view/13279
Article
Synthesis and characterization of inner-sphere substitution products in azide-containing сobalt(III) dioximates
Abstract
New compounds of Co(III) dimethylglyoximate with the sulfanilamide derivative [Co(N3)(DmgH)2(SAM)] (DmgH– is the dimethylglyoxime monoanion, and SAM is–NH2–C6H4–SO2–NH–R) are synthesized using the structural block [Co(N3)(DmgH)2(Н2О)] as the initial one. The reaction products of various [Co(N3)(DmgH)2(SAM)] with ligand L (L is pyridine (Py), thiourea (Thio), triphenylphosphine (PPh3), nicotinamide (Nia), iso-nicotinamide (INia), isonicotinic acid (НINА), 4-pyridinaldoxime (4-PaoH), 4,4’-bipyridine (Bipy), and NH4NCS) are synthesized. The compounds are studied by IR and NMR spectroscopy and X-ray diffraction analysis (CIF files CCDC 1414767–1414775 (I, V–XII)). The following facts are established. First, only the coordinated water molecule in [Co(N3)(DmgH)2(Н2О)] is replaced by SAM. Second, SAM from different similar compounds also undergoes substitution by the aforementioned organic ligands. The exception is the compound obtained by the reaction of [Co(N3)(DmgH)2(SAM)] with NH4NCS, due to which the NCS– anion replaces both SAM and inorganic anion N3-. The X-ray diffraction analysis shows that the substitution reactions give both mononuclear compounds [Со(N3)(DmgH)2(Py)], [Со(N3)(DmgH)2(PPh3)], [Со(N3)(DmgH)2(Thio)], [Со(N3)(DmgH)2(Nia)] [Со(N3)(DmgH)2(INia)], [Со(N3)(DmgH)2(HINА)] ∙ H2O, [Со(N3)(DmgH)2(4-PaoH)] ∙ DMF, and [Со(N3)(DmgH)2(Bipy)] and binuclear molecular complexes [(Со(N3)(DmgH)2)2(Bipy)] ∙ 0.5H2O and [(Со(N3)(DmgH)2)2(Bipy)] ∙ H2O, as well as ionic complex (NH4)[Co(SCN)2(DmgH)2] ∙ 3H2O. The obtained compounds supplement a series of complexes that make it possible to evaluate the trans effect of the N3- anion on the bond lengths along the axial coordinate and on the Со–N bonds in the equatorial plane of the octahedron.
516-538
Synthesis, characterization, and crystal structure of cobalt(II) and zinc(II) complexes with a bulky Schiff base derived from rimantadine
Abstract
Two novel complexes, C38H48CoN2O2 (I) and C38H48N2O2Zn (II), were prepared through an analogous procedure with a corresponding metal chloride and a bulky Schiff base ligand (HL) which derived from rimantadine and salicylaldehyde in appropriate solvents, respectively. They were structurally characterized by the means of IR, UV-Vis, elemental analysis, molar conductance, PXRD and single-crystal X-ray diffraction (CIF files nos. 946735 (I), 893304 (II)). Single-crystal X-ray diffraction analysis reveals that I belongs to the triclinic system, \(P\overline 1 \) space group; each asymmetric unit consists of one cobalt(II) complex and one lattice ethanol molecule. In each complex molecule, cobalt(II) atom is four-coordinated via two oxygen atoms and two nitrogen atoms from the deprotonated Schiff base ligands, forming an approximate planar geometry. The crystal structure also involves strong O–H···O intermolecular hydrogen bonds between the solvent alcoholic and phenol O atoms of complex molecule. Complex II belongs to the monoclinic system, Cc space group. Each asymmetric unit consists of one zinc(II) ion and two deprotonated ligands. Zinc(II) atom lies on a twofold rotation axis and is four-coordinated via two nitrogen atoms and two oxygen atoms from the Schiff base ligands, forming a distorted tetrahedral geometry.
539-545
Two heterometallic complexes with a new macrocyclic oxamido complex ligand
Abstract
A new macrocyclic oxamido-nickle(II) complex Na2NiL was synthesized. L denotes the doubly deprotonated forms of (13Z, 19Z)-16-methyl-6,7-dioxo-5,6,7,8-tetrahydrotriben-zo[b,f,l][1,4,8,11]tetraazacyclotetradecine- 13,20-dicarboxylate. Based on the complex ligand Ni(L2–), two heterometallic complexes [Ca2(NiL)2(H2O)8] · 10H2O (I) and [Co(NiL)2(H2O)2][Co(H2O)6] · 2.8H2O (II) were prepared. X-ray single crystal analyses (CCDC nos. 914618 (I), 914616 (II)) revealed that [Ca2(NiL)2(H2O)8] in I is a molecular box and the trinuclear complex anion [Co(NiL)2(H2O)2]2–in II is centrosymmetric. Thermogravimetric analyses showed that I exhibited moderately good stability and Co(II) catalyzed the thermal decomposition of II.
546-556
Effect of the counterion and guest molecules on the crystal structures of the coordination compounds with the Cu2(HL)22+ cation (H2L = 4,4’-[2-(3-hydroxyiminobutyl)imino]biphenyl): Syntheses, structures, and magnetic properties
Abstract
The molecular and crystal structures of complexes [Cu2(HL)2(CH3OH)2](BF4)2 ∙ C6H3Cl3 (I), [Cu2(HL)2(H2O)2](1,4-O2CС6Н4CO2) (II), and [Cu2(HL)2(H2O)2](4,4’-O2CС6Н4С6Н4CO2) (III) (H2L is 4,4’-[2-(3-hydroxyiminobutyl)imino]biphenyl, C6H3Cl3 is 1,2,4-trichlorobenzene) are determined by X-ray diffraction analyses. The crystalline lattices of complexes I and II contain discrete binuclear cations Cu2(HL)22+, whereas the crystalline lattice of compound III contains both discrete cations Cu2(HL)22+ and polymer chains [Cu2(HL)22+]n. In compounds I–III, the crystalline lattice units are joined by hydrogen bonds. The analysis of the temperature dependence of the magnetic susceptibility shows that the magnetic properties of compound III are determined only by antiferromagnetic interactions of the Cu2+ ions within the cations Cu2(HL)22+
487-493
Supramolecular complexes [M{NH(CH2)4O}{S2CN(C2H5)22] ∙ CCl4 (M = Zn or 63Cu(II)): Synthesis, structures, spectral and thermal properties
Abstract
Solvated adducts of diethyldithiocarbamate complexes of zinc and copper(II) of the formula [M{NH(CH2)4O}{S2CN(C2H5)22] ∙ CCl4 (M = Zn (I) and 63Cu (II)) were obtained. 13C MAS NMR experiments revealed magnetic nonequivalence in the dithiocarbamate moieties of the adduct isomers, the morpholine heterocycles, and the outer-sphere solvate molecules. The rhombic anisotropy of the EPR parameters of magnetically diluted isotope-substituted complex II is due to the copper polyhedron geometry, which is intermediate between a tetragonal pyramid and a trigonal bipyramid, with the ground state of the unpaired electron resulting from the mixing \(3{d_{{x^2} - {y^{2 - }}}}\) of and \(3{d_{{z^{2 - }}}}\) of copper(II). According to X-ray diffraction data, complex I is a supramolecular complex combining structurally nonequivalent adduct molecules (A and B) and “guest” molecules (CCl4). In addition, the crystal lattice has an array of channels occupied by outersphere solvate CCl4 molecules (a structural type of lattice clathrates). An STA study of the thermal properties revealed three main thermolysis steps: desorption of the solvate CCl4 molecules, elimination of coordinated morpholine molecules, and thermolysis of the dithiocarbamate moiety of the adduct.
494-501
Anion-directed assembly of two novel cadmium(II) complexes containing 2,2’-(1,4-propylene)bis(1H-benzimidazole) ligand
Abstract
Two novel inorganic-organic hybrids, {[Cd(C3BIm)(Bdc)] ∙ H2O}n (I) and {[Cd(C3BIm)(Btc)] ∙ 4H2O}n (II) {H2C3BIm = 2,2′-(1,3-propylene)bis(1H-benzimidazole), H2Bdc = benzene-1,3-dicarboxylic acid, and H3Btc = benzene-1,3,5-tricarboxylic acid}, have been prepared under specific reaction temperature and ratio of reactants. Their characterization included IR, TGA, and single-crystal X-ray diffraction analysis (CIF files CCDC. nos. 801661 (I), 801662 (II)). Both complexes I and II exhibit two-dimensional puckered hexagonal (6,3) sheets structurally, whose 3-connecting nodes are provided by H2C3BIm, H2Bdc, Cd2+ (I) and H2C3BIm, H2Btc, Cd2+ (II), respectively. Furthermore, both compounds show intense luminescence at room temperature.
502-508
High-spin adducts of redox active 2,4,6,8-tetrakis(tert-butyl)phenoxazin-1-one with tetrahedral cobalt(II) complexes
Abstract
The complex formation between redox active 2,4,6,8-tetrakis(tert-butyl)phenoxazin-1-one (L) and four-coordinate Co(II) complexes, resulting in six-coordinate adducts (I) (C77H82N12O5Co) and (II) (C38H41NO6F12Co) was studied. High-spin structure of the formed cobalt adducts I and II (hs-CoII–BQ) was established by X-ray diffraction analysis and magnetochemistry methods. Adducts I and II are stable over a wide temperature range (5–300 K) and are not involved in the redox process giving low-spin adducts (ls-CoIII–SQ) studied previously.
509-515