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Porphyrin nanostructures are widely used in the field of visible light catalysis due to their superior light absorption properties and good controllability in size, shape and function. In this paper, the development of various morphologies in three types of porphyrins with three different phenyl substituents (designated as H2TTP, H2TPP and H2TCPP, respectively) is demonstrated. The formation mechanism proposed was based on the evolution of morphology as functions of molecular structure and solvent mixture. These nano/micro assemblies are well characterized by SEM, IR, UV-vis, X-ray diffraction and photoelectric conversion. The photocatalytic oxidation reactions under visible light irradiation of 1,5-dihydroxynaphthalene (DHN) in water is utilized to evaluate the photoactivity of the as-prepared porphyrin assemblies. The photocatalytic results indicate that the obtained porphyrin assemblies exhibit enhanced visible-light photocatalytic activity. In addition, the photocatalyst is easy to separate and recover, and has good stability. The possible photocatalytic degradation mechanism of DHN by the porphyrins nanopolyhedron photocatalyst was also proposed.

The first 5,10,15,20-tetra-(4-(triazol-1-yl)phenyl) porphyridine complex, [Zn[Formula: see text]Cl[Formula: see text](5,10,15,20-tetra-(4-(triazol-1-yl)phenyl)porphyridine)][Formula: see text]Cl•[Formula: see text]H[Formula: see text]O•7[Formula: see text]H[Formula: see text]O (1) has been synthesized via solvothermal reactions and characterized by single-crystal X-ray diffraction. Complex 1 is characteristic of a one-dimensional (1-D) structure, consisting of neutral [Zn[Formula: see text]Cl[Formula: see text](5,10,15,20-tetra-(4-(triazol-1-yl)phenyl) porphyridine)][Formula: see text] chains, isolated chloride ions and lattice water molecules. The zinc ion is in a four-coordinated tetrahedral geometry, and the porphyrin macrocycle is saddle-distorted. Photoluminescence measurement with solid-state samples discovers that it exhibits an emission in the green region of the light spectrum. Time-dependent density functional theory (TDDFT) calculation discovers that this emission can be attributed to the [Formula: see text]–[Formula: see text]* charge transfer. The cyclic voltammetry (CV) measurement reveals that it possesses an oxidation peak at 0.37 V.

A manganese complex with mixed ligands, [Mn(2,2′-biim)2(4,4′-bipy)] n[Mn(2,2′-biim)3]2 n6 n(ClO4)•8 nH2O (2,2′-biim = 2,2′-biimidazole; 4,4′-bipy = 4,4′-bipyridine), has been obtained by a hydrothermal procedure and its structure determined by single-crystal X-ray crystallography. A two-dimensional (2-D) supramolecular layer is established through hydrogen-bonding interactions. Solid-state photoluminescence measurement reveals that this complex shows a blue light emission. Solid-state diffuse reflectance determination uncovers the presence of a narrow optical band gap of 2.18 eV in this complex.

Two novel porphyrinic compounds, {Zn[TCPP(CH2CH3)2(CH3)2]} n ( 1 ) and TCPP(CH3)4 ( 2 ) (TCPP = meso -tetra(4-carboxyphenyl)porphyrin), with the TCPP(CH2CH3)2(CH3)2 and TCPP(CH3)4 generated in situ , have been synthesized via a solvothermal reaction and structurally characterized by single-crystal X-ray diffraction. Compound 1 is characteristic of a two-dimensional (2-D) coordination polymer, based on the zinc ion coordinating to four nitrogen atoms and two oxygen atoms. Compound 1 possesses a large void space (220 A3) corresponding to 4.6% of the unit-cell volume. Compound 2 is characterized by an isolated structure. The reaction mechanism of preparing both compounds was explored. The photoluminescence properties, FT-IR, UV-vis absorption spectra, fluorescence lifetime and fluorescence quantum yield of TCPP were also reported.

A novel bismuth biimidazole compound, [(BiCl4 )-(μ2 -Cl)2 -(BiCl4 )][(CH3 )4 -2,2'-biimidazole]2 (1) with the (CH3 )4 -2,2'-biimidazole moiety generated in situ, was successfully prepared under hydrothermal conditions and structurally characterized using a single-crystal X-ray diffraction technique. Compound 1 is characteristic of an isolated structure, consisting of [(BiCl4 )-(μ2 -Cl)2 -(BiCl4 )] and (CH3 )4 -2,2'-biimidazole moieties. Solid-state photoluminescence measurement reveals that it shows a strong emission in the blue region. Time-dependent density functional theory studies show that this emission is ascribed to metal-to-ligand charge transfer. The solid-state diffuse reflectance spectrum reveals the existence of an optical band gap of 2.09 eV, indicating that it is a semiconductor.

A novel cadmium complex with mixed ligands {[Cd(2,2'-biim)(4,4'-bipy)(H 2 O)(ClO 4 )] (ClO 4 )} n ( 1 ) (2,2'-biim = 2,2'-biimidazole; 4,4'-bipy = 4,4'-bipyridine) has been synthesized through hydrothermal reaction and its crystal structure was determined by single-crystal X-ray diffraction technique. Single-crystal X-ray diffraction analyses revealed that complex 1 crystallizes in the space group Pna 2 1 of the orthorhombic system and exhibits a one-dimensional zigzag chain structure consisting of [Cd(2,2'-biim)(4,4'-bipy)(H 2 O)(ClO 4 )] n n + cationic chains and isolated ClO 4 – anions. Powder photoluminescent characterization reveals that complex 1 has an emission in the green region of the spectrum. Time-dependent density functional theory (TDDFT) calculation showed that the nature of the photoluminescence of complex 1 is originated from the ligand-to-ligand charge transfer (LLCT; from the HOMO of the perchlorate anions to the LUMO of the 4,4'-bipy ligand). A wide optical band gap of 3.25 eV was found by the solid-state UV/vis diffuse reflectance spectrum.

A novel ligand, diethylenetriamine-N,N′,N″-tri(acetyl-p-hydroxybenzoyl hydrazine)-N,N″-bisacetic acid, and its three soluble non-ion transition metal complexes, ML· nH2O (M = Mn, n = 4; M = Co, Ni,...

A novel ligand, diethylenetriamine-N,N″-bis(acetyl-m-hydroxybenzoyl hydrazine)-N, N′, N″-triacetic acid (H3L), was synthesized and characterized on the basis of elemental analysis, molar conductivities, 1H NMR, FAB-MS, TG-DTA analysis, and IR methods. Its complex of Gd(III) holding promise of magnetic resonance imaging(MRI) was synthesized, and relaxivity of GdL and Gd(DTPA)2– used as compare were determined in water solution, respectively. The relaxivity of GdL (R1 = 6.02 L·mmol–1·s–1) was larger than that of Gd(DTPA)2–(R1 = 4.34L·mmol–1·s–1). The relaxivity of GdL had also been investigated in human serum albumin (HSA) solution, the relaxivity of GdL was enhanced from 6.02 L·mmol–1·s–1 in water solution to 7.10 L·mmol–1·s–1 in HSA solution. In addition, thermodynamics stability constant of GdL complex was determined. The results showed that GdL is a prospective MRI contrast agent, although the thermodynamic stability constant of GdL complex(K GdL = 1019.92) was a little less than that of Gd(DTPA)2–(KGd-...

A novel ligand (H3L), diethylenetriamine-N,N″-bis(acetyl-o-hydroxybenzoyl hydrazide)-N, N′, N″-triacetic acid and its four rare earth (La, Eu, Gd, Tb) complexes have been synthesized and characterized on the basis of elemental analyses, molar conductivities, 1H NMR spectra, FAB-MS, TG-DTA analysis, and IR spectra. In addition, relaxivity (R1) of complexes are determined. The relaxivity of LaL, EuL, GdL, TbL, and Gd(DTPA)2– used as a control are 0.94, 2.79, 6.39, 1.59, and 4.34 L·mmol−1·s−1, respectively. The spin-lattice relaxivity of GdL is larger than that of Gd(DTPA)2−. The results showed that complex of GdL may be a potential magnetic resonance imaging contrast agent.

A novel bismuth biimidazole compound, [(BiCl

In this paper, two novel ligands (H3L1, H2L2) have been synthesized from diethylene triamine pentaacetic acid (DTPA) and isoniazid in different conditions. H3L1 has three carboxylic groups, and H2L2 has two carboxylic groups. Their non-ion complexes of GdL1 and MnL2 holding promise of magnetic resonance imaging (MRI) are synthesized, and relaxivity of complexes are determined, respectively. The relaxivity of GdL1 (R1 = 6.07 L·mmol−1·s−1) and MnL2 (R1 = 6.94 L·mmol−1·s−1) are larger than that of Gd(DTPA)2− (R1 = 4.34 L·mmol− 1·s−1). It is more significative that relaxivity of MnL2 is larger than that of GdL1. The results showed that two non-ion complexes are prospective MRI contrast agents.

A novel ligand (H2L), diethylenetriamine-N,N′,N′′-triacetylisoniazide N,N′′-bisacetic acid, and its four non-ion transition metal complexes, ML · nH2O (M = Mn, n = 4; M = Co, Ni, n = 2; M = Cu, n = 1), have been synthesized and characterized on the basis of elemental analysis, molar conductivity, 1H-NMR, FAB-MS, TG-DTA analysis and IR spectrum. In addition, relaxivity (R1) of the complexes was determined, the relaxivity of MnL, CoL, NiL, CuL as well as Gd(DTPA)2− used as a control are 6.94, 2.79, 2.52, 1.59 and 4.34 l mmol−1 s−1, respectively. The relaxivity of MnL is larger than that of Gd(DTPA)2−. The results show that the complex of MnL may be a potential MRI contrast agent.

A novel ligand, diethylenetriamine-N,N''-bis(acetyl-isoniazid)-N,N',N''-triacetic acid (H(3)L) has been synthesized from diethylene triamine pentaacetic acid (DTPA) and isoniazid. Ligand and its five neutral rare earth (RE=La, Sm, Eu, Gd, Tb) complexes holding promise of magnetic resonance imaging (MRI) were characterized on the basis of elemental analysis, molar conductivity, (1)H-NMR spectrum, FAB-MS, TG-DTA analysis and IR spectrum. The relaxivity (R(1)) of complexes and Gd(DTPA)(2-) used as a control were determined. The relaxivity of LaL, SmL, EuL, GdL, TbL and Gd(DTPA)(2-) were 0.14, 1.66, 3.14, 6.08, 2.79 and 4.34 l.mmol(-1).s(-1), respectively. The spin-lattice relaxivity of GdL was larger than that of Gd(DTPA)(2-). The relaxivity of GdL had also been investigated in human serum albumin (HSA) solution, the relaxivity of GdL was enhanced from 6.08 l.mmol(-1).s(-1) in water solution to 9.09 l.mmol(-1).s(-1) in HSA solution. In addition, thermodynamics stability constant of GdL complex was determined, the thermodynamic stability constant of GdL complex (K(GdL)=10(20.84)) was a few larger than that of Gd(DTPA)(2-) (K(Gd-DTPA)=10(20.73)). The results showed that complex of GdL may be a prospective MRI contrast agent with low osmotic pressure due to non-ion complex, high spin-lattice relaxivity, good stability and binding affinity for the serum protein.

A novel ligand, diethylenetriamine-N,N''-bis(acetyl-p-hydroxybenzoyl hydrazine)-N,N',N''-triacetic acid (H3L) was synthesized and characterized on the basis of elemental analysis, molar conductivity, 1H-NMR spectrum, FAB-MS, TG-DTA analysis and IR spectrum. Its complex of Gd(III) holding promise of magnetic resonance imaging (MRI) was synthesized, and relaxivity (R1) of complex and Gd(DTPA)2- used as a control was determined in water solution, respectively. The relaxivity of GdL (R1 = 6.39 l.mmol(-1).s(-1)) was larger than that of Gd(DTPA)2- (R1 = 4.34 l.mmol(-1).s(-1)). The relaxivity of GdL has also been investigated in human serum albumin (HSA) solution, the relaxivity of GdL was enhanced from 6.39 l.mmol(-1).s(-1) in water solution to 7.69 l.mmol(-1).s(-1) in HSA solution. In addition, thermodynamics stability constant of GdL was determined. The results showed that complex of GdL is a prospective MRI contrast agent, although the thermodynamic stability constant of GdL complex (K(GdL) = 10(19.56)) was a little less than that of Gd(DTPA)2- (K(Gd-DTPA) = 10(20.73)).

A novel 6-hydroxy chromone-3-carbaldehyde benzoyl hydrazone ligand and its four complexes, [LnL2(NO3)2]NO3 [Ln = Eu(1), Sm(2), Tb(3), Dy(4)], were synthesized. The complexes were characterized by the elemental analyses, molar conductivity and IR spectra. The crystal and molecular structure of Sm(III) complex was determined by single-crystal X-ray diffraction: crystallized in the triclinic system, space group P-1, Z = 1, a = 11.037(4) A, b = 14.770(5) A, c = 15.032(7) A, α = 60.583(4), β = 75.528(7), γ = 88.999(4), R1 = 0.0349. The fluorescence properties of complexes in the solid state and in the organic solvent were studied in detail, respectively. Under the excitation of ultraviolet light, strong red fluorescence of solid europium complex was observed. But the green fluorescence of solid terbium complex was not observed. These observations show that the ligand favor energy transfers to the emitting energy level of Eu3+. Some factors that influence the fluorescent intensity were also discussed.