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Chemical modification of a biopolymer offers a simple strategy to realize new materials with added benefits. In this paper, meso-tetrakis(2,4,6-trimethylphenyl) porphyrinto) zinc(II) supported sodium alginate gel beads were successfully prepared, characterized, and used for the removal of a cationic dye from aqueous solution. The chemical structure of the prepared composite beads was confirmed by FT-IR, SEM, XRD and TGA/DTG techniques. Analytical data suggested that the sodium alginate beads and meso-tetrakis(2,4,6-trimethylphenyl) porphyrinto) zinc(II) complex interacted via non-covalent interaction (H-bonding) mode. The morphological micrographs showed spherical and smooth composite beads. The crosslinking of hydroxyl and carboxylate groups of the biopolymer with calcium ions and the incorporation of meso-tetrakis(2,4,6-trimethylphenyl) porphyrinto) zinc(II) into alginate matrix resulted in a small decrease of residual mass. The maximum adsorption capacities of methylene blue, at 20 °C, were found to be 52.3 mg/g and 34.8 mg/g for sodium alginate composite beads (3%) and plain sodium alginate beads, respectively. The adsorption process followed Freundlich isotherm and pseudo second order kinetics. The thermodynamic study displayed an exothermic and non-spontaneous process.

A new pyrazole-tethered thiazolidine-2,4-dione derivative (8) has been synthesized by the Knoevenagel condensation of 3-(4-nitrophenyl)-1-phenyl-1H-pyrazole-4-carbaldehyde (4) and 3-(2,4-dioxothiazolidin-3-yl)propanenitrile (7). The structure of the final compound was confirmed by standard spectroscopic techniques including IR spectroscopy, 1H-NMR spectroscopy, and ESI-MS mass spectrometry. Molecular features including frontier molecular orbital (HOMO-LUMO) energies, reactivity descriptors and molecular electrostatic potential (ESP) of the title molecule were determined using density functional theory (DFT) calculation. The in vitro cytotoxicity of both the intermediate (4) and final (8) compounds were investigated against cancerous (SW-480 and MCF-7) and normal (HEK-293) cell lines by MTT assay. Compound (8) displayed higher activity than (4) with higher sensitivity against breast cancer cell line and lesser toxicity. The experimental data were further complemented by docking and absorption, distribution, metabolism, and excretion (ADME) studies. Communicated by Ramaswamy H. Sarma

Despite the interesting structure of the generic thiacalix[4]arene containing four coordinating sulfur atoms bridging four phenolic units, there are only a few reported examples of thiacalixarene-based coordination complexes that are used as electrocatalysts. Herein, we report electrocatalytic hydrogen evolution reaction (HER) by a thiacalix[4]arene-based copper(II) complex (1). As expected, two reduction waves were appeared (-0.48 V and -1.30 V vs Ag/AgCl) for Cu2+/Cu+ and Cu+/Cu reduction couples. The HER by proton reduction occurs at -1.03 V with a shift of 0.27 V compared to the second peak potential at -1.30 V. The increase in the number of acetic acid equivalents, from 0 to 17.5 with a frequency of 2.5 eq, was accompanied by an increase in the peak current that reached a maximum value of 183 and#181;A for 15 equivalents of acetic acid.

In this investigation, Pergularia tomentosa leaves were used as a promising source of bioproducts for the reduction of copper sulfate into copper oxide nanoparticles. The prepared nanoparticles were characterized using Fourier-transform infrared spectroscopy (FT-IR), X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Transmission electron microscopy (TEM), and Thermogravimetric analysis (TGA). FI-IR showed the presence of hydroxyl, ester, and aromatic groups, which are characteristics of phenolics and other bioproducts. SEM features exhibited spherical and agglomerated particles. In EDX data, the peak at 1 Kev, is an index of metallic nanoparticles of copper. The signals related to C and O peaks indicated the presence of phytochemicals in the studied extract. The synthesized copper oxide nanoparticles had a face-centered cubic structure. The size of the nanoparticles varied from 1.7 to 15.2 nm. The adsorption capacity of methylene blue using copper oxide nanoparticles reached 93.2 mg/g (pH = 6, T = 22 °C, adsorbent dose = 0.0125 g). Additionally, methylene blue solution was completely decolorized after 2 min of reaction (pH = 6, 0.0057 mg NaBH4, C0 = 10 mg/L, catalyst = 0.005 g). NOVELTY STATEMENTIn this study, Pergularia tomentosa leaves were used, for the first time, as a biomaterial rich in bioproducts for the reduction of copper sulfate into copper oxide nanoparticles. The prepared particles act as promising materials for the decolorization of contaminated water via both adsorption and degradation processes.

Functionalization and various applications of biomaterials have progressively gained a major interest due to the cost-effectiveness, renewability, and biodegradability of these substrates. The current work focalized on the functionalization of microcrystalline cellulose with polyethyleneimine solution (3 %, 5 %, and 10 %) and hydrazine sulfate salt (1:1, 1:2, 2:1) using an impregnation method. Untreated and treated samples were characterized using FT-IR, SEM, XRD, TGA, and DTA analyses. The crystallinity index values for control microcrystalline cellulose, cellulose-polyethyleneimine, and cellulose-hydrazine were 57.13.8 %, 57.29 %, and 52.62 %, respectively. Cellulose-polyethyleneimine (5 %) and cellulose-hydrazine (1:1) displayed the highest adsorption capacities for calmagite (an anionic dye). At equilibrium, the maximum adsorption capacities for calmagite achieved 104 mg/g for cellulose-polyethyleneimine (5 %), 45 mg/g for cellulose-hydrazine (1:1), and only 12.4 mg/g for untreated cellulose. Adsorption kinetics complied well with the pseudo-second-order kinetic model. The adsorption isotherm fitted well with the Langmuir isotherm. Overall, the functionalized cellulosic samples could be considered potential materials for the treatment of contaminated waters.

In this work, pectin biopolymers were functionalized with dichloride (5,10,15,20-tetraphenylporphyrinato) antimony [Sb(TPP)Cl2] at various compositions (0.5%, 1%, and 2%). The prepared compounds were characterized with several analytical methods, including X-ray fluorescence (XRF) spectrometry, Fourier-transform infrared spectroscopy (FT-IR), electrospray ionization mass spectrometry (EIS), scanning electron microscope (SEM), X-ray diffraction (XRD), and thermogravimetric-differential thermal (TGA/DTG) analysis. The XRF technique evidenced the presence of Sb metal in the composite beads. FT-IR suggested that the interaction between pectin and the [Sb(TPP)Cl2] complex was assured by inter- and intramolecular C-H⋯O, C-H⋯Cl hydrogen bonds and weak C–H⋯Cg π interactions (Cg is the centroid of the pyrrole and phenyl rings). The morphological features of the prepared polymeric beads were affected by the addition of [Sb(TPP)Cl2] particles, and the surface became rough. The thermal residual mass for the composite beads (29%) was more important than that of plain beads (23%), which confirmed the presence of inorganic matter in the modified polymeric beads. At 20 °C, the highest adsorption amounts of methylene blue were 39 mg/g and 68 mg/g for unmodified pectin and pectin-[Sb(TPP)Cl2] beads, respectively. The adsorption mechanism correlated well with the kinetic equation of the second order and the isotherm of Freundlich. The prepared polymeric beads were characterized as moderate-to-good adsorbents. The calculated thermodynamic parameters demonstrated an exothermic and thermodynamically nonspontaneous mechanism.

A new pyrazole-tethered thiazolidine-2,4-dione derivative (

In this paper we reported on the spectroscopic, physicochemical and the catalytic properties of dichloride (5,10,15,20-tetraphenylporphyrinato)antimony(V) hexachloridoantimonate(V) [Sb(TPP)Cl2] SbCl6(2). Optical spectroscopy data showed a red-shift of both absorption bands; the Soret and the Q, which was observed of the antimony complex compared with that free base porphyrin H2TPP. The optical gap Eg-op was calculated using the Tauc plot method suggesting a semi-conductor product. The [Sb(TPP)]+ and the [Sb(TPP)Cl2]+ fragments were determined using the mass spectrometry. The fluorescence investigation showed a high fluorescence quantum yield with a lifetime of (2) compared to the free base porphyrin.32% of the calmagite solution was removed (C0 = 40 mg/L, pH = 6, mass = 3 mg) using (1). However, using the system (2)/H2O2 (C0 = 40 mg/L, pH = 6, t = 240 mins), the yield value of decolourisation was found to be 94% at equilibrium.

A new metalloporphyrin (4,4′-bipyridine)meso-tetrakis(2,4,6-trimethylphenyl) porphyrinato) zinc(II) ([Zn(TMP)(4,4′-bpy)]) (3) was obtained by reacting meso-tetrakis(2,4,6-trimethylphenyl)porphyrinato) zinc(II) [Zn(TMP)] (2) and 4,4′-bipyridine (4,4′-bpy). The starting material meso-tetrakis(2,4,6-trimethylphenyl)porphyrine (H2TMP, 1) as well as complexes (2 and 3) were characterized by the means of microanalysis, 1H NMR, and ESI-MS techniques. The molecular structure of the final complex (3) was also confirmed by single crystal X-ray crystallography. Detailed photo-physical and electrochemical properties of the complexes were also determined. The oxidative degradation ability of complexes (2 and 3) was evaluated and compared against an organic dye (calmagite). When used as catalyst, complex (2) showed better efficiency ~ 48% than the complex (3) (41%). Overall, this work not only explores the ability of metalloporphyrin to degrade organic dyes in aqueous solution, but also showed that the degradation ability of a metalloporphyrin complex can be fine-tuned by varying axial ligand.

In this investigation

Cellulose substrate waste has demonstrated great potential as a biosorbent of pollutants from contaminated water. In this study, Nerium oleander fruit, an agricultural waste biomaterial, was used for the biosorption of methylene blue from synthetic solution. Fourier-transform infrared (FTIR) spectroscopy indicated the presence of the main absorption peak characteristics of cellulose, hemicellulose, and lignin compositions. X-ray diffraction (XRD) pattern exhibited peaks at 2θ = 14.9° and 2θ = 22°, which are characteristics of cellulose I. Scanning electron microscopy (SEM) showed a rough and heterogeneous surface intercepted by some cavities. Thermogravimetric analysis (TGA) showed more than a thermal decomposition point, suggesting that Nerium fruit is composed of cellulose and noncellulosic matters. The pHpzc value of Nerium surface was experimentally determined to be 6.2. Nerium dosage, pH, contact time, dye concentration, and temperature significantly affected the adsorption capacity. The adsorption capacity reached 259 mg/g at 19 °C. The mean free energy ranged from 74.53 to 84.52 KJ mol−1, suggesting a chemisorption process. Thermodynamic parameters define a chemical, exothermic, and nonspontaneous mechanism. The above data suggest that Nerium fruit can be used as an excellent biomaterial for practical purification of water without the need to impart chemical functionalization on its surface.

Thiacalix[4]arene with four sulfur-bridging atoms and four hydroxy coordinating groups in the lower rim is a promising candidate for powerful electrocatalytic hydrogen production. However, there are only a few examples reported in the literature where conjugated thiacalix[4]arene is used as a pre-catalyst for the hydrogen evolution reaction. The present work evaluates the electrocatalytic performance of a nickel(II) coordination complex based on generic thiacalix[4]arene. The coordination complex is characterized by cyclic voltammetry, where two reduction peaks are observed at −0.57 and −1.33 V for the two redox couples Ni2+/Ni+ and Ni+/Ni, respectively. The proton reduction occurs at the second peak potential with a slight shift at about −1.0 V, with increasing peak currents directly related to the number of acetic acid equivalents. The maximum peak current was observed to be at about 67 µA for 20 equiv. of acetic acid.

In the present work, we report synthesis, structural elucidation and photophysical properties of new pentacoordinated Zn(II) porphyrinates (1-2). Complexes with formula [Zn(TEBOP)(DABCO)](DABCO) (1) [TEBOP = meso-tetrakis(ethyl-4(4-butyryl)oxyphenyl) porphyrinato), DABCO = 1,4-diazabicyclo [2.2.2] octane], and (2) [Zn(TEBOP)(pyz)] [pyz = pyrazine] have been studied to explore the effects of axial ligand on the structural and photophysical properties of [Zn(TEBOP)]. Both the solution and solid-state characterization unambiguously confirmed the pentacordinated nature of the complexes 1 and 2. The X-ray molecular structures showed that these complexes exhibited high ruffling deformation. We showed here that some of the optical properties (absorption features and quantum yield) could be modulated by varying the axial ligand whereas emission wavelength (λem) and lifetime (τf) values were found to remain unchanged. Electrochemical studies suggested that the characteristic reduction and oxidation potentials of the porphyrin ring varied with the axial ligand. Finally, [Zn(TEBOP)] and complexes 1 and 2 were checked for the oxidative degradation of methylene blue (C0 = 30 mg/L, T = 22°C, pH = 6, H2O2 = 4 mL/L). The degradation yields followed the order: [Zn(TEBOP)] + H2O2 (47%) > 2 (38.5.9%) > 1 (26.9%).

International audience; This work focuses on new materials based on the addition of zinc as specifically metal centers for the capture of NO2 gas with DFT calculations. This study aims at the synthesis and the spectroscopic characterizations of the free base meso-tetrakis-,(3,4,5trimethoxyphenyl)porphyrin (H2TTMP) (I), meso tetrakis(3,4,5trimethoxyphenyl)porphyrinato)zinc(II) complex [Zn(TTMP)] (II) and the (4-cyanopyridine) meso-tetrakis - (3,4,5-trimethoxyphenyl)porphyrinato)zinc(II) [Zn(TTMP)(4-CNpy)] (III). X-ray molecular structure of (III) displays that the crystal lattice of the five-coordinated zinc(II) coordination compound, is made up of two dimensional layers parallel to the [0 0 1] direction sustained by CH⋯Cg and Cg⋯Cg π inter and intra-molecular interactions. Notably, the presence of voids of 1.2 Å and a grid of 0.7 Å are located between the 2D layers. DFT calculations on the three porphyrin derivatives were carried out and results indicated an agreement with both IR and UV-vis experimental data. The adsorption behaviors of the toxic NO2 gas molecules on the porphyrin derivatives were investigated using first-principles density functional theory. Based on the MEP of (I)–(III) molecules and the MEP of NO2 and the calculation of the adsorption energies, we suggest that compound (II) has the best attraction. More importantly, after NO2 chemi-sorption on porphyrin derivatives, a remarkable red-shift is observed in the optical spectra, especially for II/NO2 complex, thus offering a good index to detect the binding of NO2. The optical spectra can therefore be used to detect the presence of NO2 and porphyrin derivatives indicate appropriate properties to establish good NO2 sensors.

The design of metalloporphyrins has attracted the attention of scientists owing to their valuable properties. In this work, the synthesis of meso-tetraphenyl porphyrin H2TPP (I), meso-tetraphenylporphyrinato-chromium(III) complex [CrIII(TPP)Cl] (II), and bis(cyano) meso-tetraphenylporphyrinato-chromium(III) complex [K(2 2 2)] [CrIII(TPP)(CN)2] 2.(C7H6O2) (III) was described. The physicochemical properties of (ll)-(IIII) were investigated. X-ray molecular structure of (III) displayed that the crystal lattice of the six-coordinated chromium (III) coordination compound, was made by two-dimensional chain pairs parallel to the [0 1 0] direction sustained by C__H…Cg and Cg…Cg π inter and intra-molecular interactions. Hirshfeld surface analysis allowed us to understand the intermolecular contacts, where the fingerprint plot provided the information about the percentage contribution. UV–vis data showed a red-shift for the chromium complex and slightly blue-shift after coordination with cyano axial ligand. The Eg-op value suggested that (I)-(III) compounds are semi-conductor. The complex (II) efficiently and promptly degraded calmagite dye solution at a yield of 100% (calmagite = 40 mg/L, pH = 6, time = 10 min, catalyst dose = 3 mg, H2O2 dose = 4 mL/L, and T = 20 °C).

In this work, free base meso-tetratolylporphyrin H2TTP (I), meso-tetratolylporphyrinato zinc(II) [Zn (TTP)] (II), and zinc derivative (4.4′diaminodiphenylmethane) (meso-tetratolylporphyrinato) zinc {[Zn (TTP) (DADMP)2]}n (III) were successfully synthesized and characterized. Density functional theory calculations at B3LYP-D3/6-311+G (d, p) level of theory were carried out for geometric parameters. Structures of compounds (I)-(III) were studied using UV–vis, FT-IR, 1H NMR, fluorescence spectroscopy, and ESI Mass Spectrometry. The experimental data displayed good agreement with DFT-calculations results. Natural bond orbital (NBO) confirmed the stability of the obtained molecules from hyperconjugation interaction and charge delocalization. Molecular electrostatic potential (MEP) demonstrated the charge transfer and the way of interaction for (I)-(III). Frontier molecular orbitals (FMOs) showed the occurrence of charge transfer within the molecule. The optical spectra and interaction energy data confirmed a strong interaction between [Zn (TTP)] and DADMP ligand. The single structure of complex (III) indicated a building block, in solid state. The axial ligand (4.4′diaminodiphenylmethane) present as a bridge between adjacent zinc(II) consisted of 1D polymer chain along the [001] direction. The supramolecular was stabilized by weak intermolecular interactions C69–H69 … Cg7. The porphyrin core structure was practically quasi-plane. The optical spectra and interaction energy data proved the strong interaction between [Zn (TTP)] and DADMP ligand.

Cellulose substrate waste has demonstrated great potential as a biosorbent of pollutants from contaminated water. In this study, Neriumoleander fruit, an agricultural waste biomaterial, was used for the biosorption of methylene blue from synthetic solution. Fourier-transform infrared (FTIR) spectroscopy indicated the presence of the main absorption peak characteristics of cellulose, hemicellulose, and lignin compositions. X-ray diffraction (XRD) pattern exhibited peaks at 2&theta, = 14.9&deg, and 2&theta, = 22&deg, which are characteristics of cellulose I. Scanning electron microscopy (SEM) showed a rough and heterogeneous surface intercepted by some cavities. Thermogravimetric analysis (TGA) showed more than a thermal decomposition point, suggesting that Nerium fruit is composed of cellulose and noncellulosic matters. The pHpzc value of Nerium surface was experimentally determined to be 6.2. Nerium dosage, pH, contact time, dye concentration, and temperature significantly affected the adsorption capacity. The adsorption capacity reached 259 mg/g at 19 &deg, C. The mean free energy ranged from 74.53 to 84.52 KJ mol&minus, 1, suggesting a chemisorption process. Thermodynamic parameters define a chemical, exothermic, and nonspontaneous mechanism. The above data suggest that Nerium fruit can be used as an excellent biomaterial for practical purification of water without the need to impart chemical functionalization on its surface.

The synthesis, photo-physical properties and the optical spectroscopy of the starting materials H2TTP (1), [Zn(TTP)](2) and [Zn(TTP)(4,4′-bpy)]0.2(4,4′-bpy.H2O) (3) (TTP = meso-tetratolylporphyrin) are reported. The X-ray molecular structure of the compound shows that this species is a five-coordinated zinc(II) metalloporphyrin. Complex 3 crystallized in the monoclinic crystal system, space group C 2/c with a = 15.7541(2) (A), b = 18.6688(3) (A), c = 21.6410(4) (A), β = 103.025(1)°, V = 6201.08(17) (A3), dcalc, (g/cm3) = 1.327 and Z = 4. Data gleaned from the optical spectroscopy reveals that the bathochromic shift of the Soret and Q absorption bands is connected mainly to the distortion of the 24-atom average plane of the porphyrinic macrocycle and the values of the optical gap Eg-op of the metallized species (2–3) are higher than that of the free base porphyrin H2TTP. The association constant (Kas) values of the zinc bpy-TTP derivative were also determined. Further, the interaction of the studied complexes with two organic dyes, namely Acid Blue 25 and Calmagite, was performed in an aqueous medium in batch mode. The results exhibited that the removal of Calmagite and Acid Blue 25 using complex 1 are 32% and 24%(C030 mg/L, pH 6, T 25 °C). However, the target removal of these dyes using the system H2O2-complex 3 reached 46% and 35% (C0 30 mg/L, pH 6, H2O2 concentration 4 mL/L, T 25 °C).

This work reports on the synthesis and characterization of a new porphyrins complex:[Zn(TEBOP)(4,4′-bpy)](4,4′-bipyridine)(5,10,15,20-(tetraethyl-4(4-butyryl)oxyphenyl)porphyrinato)zinc(II) (3). Single crystal X-ray diffraction, photophysical and electrochemical characteristics were studied. The prepared complex, penta-coordinated zinc(II) porphyrin derivatives shows moderate ruffling distortion and the zinc atom is nearly planar with the porphyrin core. Tolyl and ethyl-4(4-butyryl)oxyphenyl) moieties at the meso positions present a bathochromic shift of the absorption bands, and a notable increase in the absorption coefficient of the Q(0,0) and Q(0,1) bands was observed with a higher fluorescence quantum yield and lifetime compared with the free base porphyrin. The electrochemical investigation shows a reversible reduction of the synthesized complexes. The catalytic power and the adsorption properties of the prepared complexes were studied for Calmagite degradation, an azoic organic dye. The results reveal that the studied compounds could be used as catalysts for the decolourisation of dyes in the presence of H2O2.

In the title dinuclear Nb(V) compound, [Nb(2)(C(44)H(28)N(4))(2)O(3)], each Nb atom is seven-coordinated with three bridging O atoms and four N atoms from a chelating tetra-phenyl-porphyrinate anion. The Nb-O bond lengths range from 1.757 (6) to 2.331 (6) Å, and the average (niobium-pyrrole N atom) distance is 2.239 Å. In the dinuclear mol-ecule, the Nb⋯Nb separation is 2.8200 (8) Å, and the dihedral angle between the two porphyrinate mean planes is 5.4 (1)°. Weak inter-molecular C-H⋯π inter-actions are present in the crystal structure.

The asymmetric unit of the title compound, [Sb(C44H28N4)Cl2][SbCl6], consists of one half of an antimony(V) tetraphenylporphyrin complex cation and one half of an hexachloridoantimonate(V) anion. In the complex cation, the SbVatom lies on an inversion center and is octahedrally coordinated by four N atoms from a macrocyclic tetraphenylporphyrinate ligand and two chloride ions. The complex cation has approximately a planar core with a maximum deviation of 0.018 (5) Å from the porphyrin mean plane. The average Sb—N distance is 2.062 (11) Å, while the Sb—Cl distance is 2.355 (1) Å. The SbVatom of the anion is also located on an inversion center. The [SbCl6]−octahedron exhibits rhombic distortion characterized by the Sb—Cl bond lengths [2.311 (3), 2.374 (2) and 2.393 (4) Å]. In the crystal, the cations and anions are linked C—H... Cl hydrogen bonds, forming a layer parallel to (211).

The asymmetric unit of the title complex, [Sb(C44H28N4)Cl2][Sb2Cl8]0.5·CH2Cl2, is composed of a SbV complex cation wherein the Sb atom is hexacoordinated by four N atoms of the pyrrole rings of the tetraphenylporphyrinate (TPP) ligands and two chloride ions, a half di-μ-chlorido-bis[trichloridoantimonate(III)] counter-anion and a dichloromethane solvent molecule. In the cation, the average Sb—N distance is 2.066 (2) Å, while the Sb—Cl distances are 2.3410 (11) and 2.3639 (12) Å. The central unit of the cation, SbN4C20, is far from being planar, with deviations of atoms from the least-squares plane ranging from −0.110 (4) to 0.124 (4) Å. The Sb—Cl distances in the anion, which is located about an inversion center, lie in the wide range 2.3715 (13)–2.7489 (13) Å, the longest distances being between the Sb and bridging Cl atoms. The crystal structure is stabilized by intermolecular C—H...Cl interactions involving the cations, the anions and the solvent molecules. The solvent molecule is disordered over two orientations in a 0.901 (13):0.099 (13) ratio.