Dong-Mei Li

meso-Tetrakis(4-N-benzylpyridyl)porphyrin and its supramolecular complexes formed with anionic metal–oxo cluster: spectroscopy and electrocatalytic reduction of dioxygen

Abstract The research results show that MTBPyP ( meso -tetrakis(4- N -benzylpyridyl)porphyrin, M=H 2 , Zn) bearing quadruply positive charges associates with an anionic metal-oxo cluster (SiW 12 O 40 xa04− ) to form a supramolecular complex in aqueous solution. The spectral evolution and Jobs plots reveal that the aggregates contain equal numbers of the cationic porphyrins and the anionic SiW 12 O 40 xa04− . The association is accompanied by significant changes in the Soret band of the individual porphyrins. The 1:1 supramolecular complex [CoTBPyP][SiW 12 O 40 ] may serve as an electrocatalyst for electrocatalytic reduction of O 2 , and more of O 2 is reduced to H 2 O at potential where the SiW 12 O 40 xa04− is in reduced state.

A metal-oxo cluster-supported transition metal complex: synthesis, structure and properties of [Cu(phen)2]2[{Cu(phen)}2Mo8O26]·H2O

Abstract [Cu(phen)2]2[{Cu(phen)}2Mo8O26]·H2O has been synthesized from MoO3, H2MoO4, Cu(Ac)2·H2O and 1,10-phenanthroline in aqueous solution using the hydrothermal method and characterized by single-crystal X-ray structure analysis. The title compound consists of a centrometric β-octamolybdate-supported complex anion [{Cu(phen)}2Mo8O26]2−, two bis-phenanthroline Cu(I) cations, and one water molecule of crystallization.

Lanthanide complexes with acetylacetonate and 5,10,15,20-tetra[para-(4-flourobenzoyloxy)-meta-ethyloxy]phenylporphyrin

Abstract Lanthanide complexes of acetylacetonate and 5,10,15,20-tetra[para-(4-flourobenzoyloxy)-meta-ethyloxy]phenylporphyrin having the general formula Ln[(FBOEP) 4 P]acac (where Ln=Ho, Er, Yb, Lu; FBOEP=[para-(4-flourobenzoyloxy)-meta-ethyloxy]phenyl; Hacac=acetylacetone; P=porphyrin) have been prepared and characterized. A structure is proposed in which one 5,10,15,20-tetra[para-(4-flourobenzoyloxy)-meta-ethyloxy]phenylporphyrin is coordinated to a rare earth ion in a tetradentate fashion, while one acetylacetonate is coordinated to the same metal ion in a bidentate fashion. We investigated the photo-generated charge behavior of the ligand and the complex, Lu[(FBOEP) 4 P]acac, by means of surface photo-voltage spectroscopy (SPS) and field induced surface photo-voltage spectroscopy (FISPS) which are useful tools to investigate the photo-physics of excited states generated by absorption in the aggregate state.

SYNTHESIS AND STRUCTURE OF A NOVEL MONONUCLEAR TUNGSTEN (VI) CITRATO COMPLEX, (NH4)3[Li(H2O)3WO3(C6 H4O7)]

Abstract The first mononuclear tungsten-citrato complex, (NH4)3[Li (H2O)3WO3(C6H4O7)] (1), has been prepared by the reaction of ammonium tetrathio tungstate and lithium citrate in CH3OH-H2O solution at pH 8.2. There are two crystallographically independent anions in the asymmetric crystallographic unit. The crystal structure of the title compound (triclinic, space group P1, a = 6.901(1), b = 15.136(3), c = 16.107(3) Å, α = 75.85(3), β = 89.89(3), γ = 89.97(3), V = 1631.4(6) Å3, R = 0.068, R W = 0.1674 for 3878 reflections with I > 2σ(I)), reveals that in the compound a tungsten atom is coordinated to a fully deprotonated citrate as a tridentate ligand and three terminal oxygen atoms to form a distorted coordination octahedron.

Synthesis of Unsymmetrical Schiff-Base Porphyrin with O-Nitrobenzaldehyde and its Lanthanide Complexes

Abstract The synthesis of a new unsymmetrical Schiff-base porphyrin is reported from 5-(p-nitrophenyl)-10, 15, 20-triphenyl porphyrin and o-nitro benzaldehyde. Its lanthanide complexes are also reported. The ligand and its lanthanide complexes are characterized by UV, IR and 1H NMR spectra.

Metal–oxo cluster-supported transition metal complexes: hydrothermal synthesis and characterization of [{M(phen)2}2(Mo8O26)] (M = Ni or Co)

Two new metal–oxo supported transition metal complexes, [{M(phen)2}2(Mo8O26) (M = Ni or Co; phen = 1,10-phenanthroline) are synthesized by a hydrothermal method and characterized by X-ray crystallography, showing that the octamolybdate possesses a novel unprecedented structure and that [M(phen)2]2+ units are covalently bonded to the [Mo8O26]4– cluster.

Hydrothermal synthesis and characterization of [Ni(phen)3]2[Mo8O26]·2H2O

Abstract The reaction of MoO3, H2MoO4 and Ni(Ac)2·6H2O with 1,10-phenanthroline by a hydrothermal method furnishes the discrete cluster [Ni(phen)3]2[Mo8O26]·2H2O (1). The structure of 1 is triclinic, space group P1, a=11.4965(10), b=11.6829(13), c=15.1518(15) A, α=83.032(8), β=71.557(7), γ=78.319(7)°, R=0.0433 for 7397 observed [I>2σ(I)] reflections. The crystallographically determined solid state structure of 1 shows that the cluster consists of two complex cations, one cluster anion [Mo8O26]4− and two water molecules of crystallization. Each nickel ion is coordinated by six nitrogen atoms from three phenanthroline ligands, forming a distorted octahedron, and the anion has a β-configuration formed by eight edge-sharing MoO6 octahedra. Compound 1 was characterized by means of elemental analysis, IR spectra and TGA analysis.

Lanthanide complexes with acetylacetonate and 5,10,15,20-tetra[para-(4-chlorobenzoyloxy)-meta-ethyloxy]-phenyl porphyrin

Abstract Lanthanide complexes of acetylacetonate and 5, 10, 15, 20-tetra[para-(4-chloro-benzoyloxy)-meta-ethyloxy]phenyl porphyrin having the general formula Ln[(ClBOEP) 4 P]acac (where Ln=Tb, Dy, Ho, Er; ClBOEP=[para-(4-chlorobenzoyloxy)-meta-ethyloxy]phenyl; Hacac=acetylacetone; P=porphyrin) have been prepared and characterized. A structure is proposed in which one 5, 10, 15, 20-tetra[para-(4-chloro-benzoyloxy)-meta-ethyloxy]phenyl porphyrin is coordinated to a rare earth ion in a tetradentate fashion, while one acetylacetonate is coordinated to the same metal ion in a bidentate fashion.

A new dinuclear molybdenum(V)-sulfur complex containing citrate ligand: Synthesis and characterization of K2.5Na2NH4[Mo2O2S2(cit)2].5H2O

The complex, K2.5Na2NH4[Mo2O2S2(cit)(2)]. 5H(2)O (1), was obtained by crystallization from a solution of (NH4)(2)MoS4, potassium citrate (K(3)cit) and hydroxyl sodium in methanol and water under an atmosphere of pure nitrogen at ambient temperature. The crystals are triclinic, space group , a = 7.376 (3)Angstrom, b = 14.620 (2) Angstrom, c = 14.661 (1) Angstrom, alpha = 71.10 (1)degrees, beta = 81.77 (1)degrees, gamma = 78.27(2)degrees, R = 0.0584 for 2545 observed (I > 2 sigma (I)) reflections. Single crystal structure analysis reveals that citrate ligand coordinated to molybdenum atom through two carboxylato oxygens and one deprotonated hydroxyl oxygen together with two bridging sulfur atoms and a terminal oxygen atom completes distorted coordination octahedron around each molybdenum atom. Principal dimensions are: Mo = O-t, 1.707 Angstrom (av); Mo-S-b, 2.341 Angstrom (av); Mo-O-(hydroxyl), 2.021 Angstrom (av); Mo-O(alpha-carboxyl), 2.1290 Angstrom (av) and Mo-O(beta-carboxyl), 2.268(av) Angstrom. IR spectrum is in agreement with the structure.

Synthesis and Characterization of a Series of Cationic Porphyrins Having Different Steric Effects

Abstract A series of cationic porphyrins having only different steric effects and their cobalt complexes were synthesized. The cations of these porphyrins are meso-tetrakis(4-N-propylpyridyl)porphyrin (TPPyP4+), meso-tetrakis(4-N-ethylpyridyl)porphyrin (TEPyP4+) and meso-tetrakis(4-N-methylpyridyl)porphyrin (TMPyP4+), respectively. The anions are I− (water soluble porphyrins) and ClO4 − (organic solvent soluble porphyrins), respectively. The synthetic cationic porphyrins were characterized by elemental analysis, UV-visible absorption spectra, FTIR, MALDI-TOF-MS and 1H-NMR spectra.