Iranian Chemical SocietyInorganic Chemistry Research2538-18651120170701Preparation of Nickel Nanoparticles by Intramolecular Reaction of Nickel(II) Hydrazine Complex in the Solid State at Room Temperature183266410.22036/icr.2016.32664ENSeyed Abolghasem Kahani*Department of Inorganic Chemistry, Faculty of Chemistry, University of Kashan, Kashan 87317-51167, IranMassumeh KhedmatiDepartment of Inorganic Chemistry, Faculty of Chemistry, University of Kashan, Kashan 87317-51167, IranJournal Article20140825Ni6(N2H4)6(SO4)4(OH)2(H2O)8](SO4)(H2O)10 complex was prepared according to literature report. The reaction between aforementioned complex via sodium alkoxides as a reactants, were carried out in the solid state. The [Ni6(N2H4)6(SO4)4(OH)2(H2O)8](SO4)(H2O)10 undergoes an intramolecular two electrons oxidation-reduction reaction at room temperature and metallic nickel nanoparticles (Ni1-Ni5) was produced. The aforesaid complex contains nickel (II) as an oxidizing agent and also hydrazine ligand as a reducing agent. Its redox reaction leads to the formation of other products, sodium azide and ammonia gas and alcohols. In such a solid state reaction, not only the intramolecular redox reaction is important but also it is a novel method in the synthesis of nanoparticles. The nickel metal nanoparticles were characterized using X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and vibrating sample magnetometer (VSM) analysis. The synthesized nickel nanoparticles have similar morphologies however the particle size distributions are different. The nickel nanoparticles have particle size distributions ranging from 10 to 75 nm. This work presents a novel approach in the intramolecular redox reactions in the solid state, and provides insight into the synthesis of metal nanoparticles via metal hydrazine complexes at room temperature.Iranian Chemical SocietyInorganic Chemistry Research2538-18651120170701Electrochemistry, Thermalanalysis, and Theoretical Study of Vanadyl Schiff Base Complexes9203322810.22036/icr.2016.33228ENAli Hossein KianfarDepartment of Chemistry, Isfahan University of Technology, Isfahan, Iran, 84156-83111Hajar Mohamadi Malek AbadiDepartment of Chemistry, Yasouj University, Yasouj, IranRoghayeh Hashemi FathDepartment of Chemistry, Yasouj University, Yasouj, IranMahmoud RoushaniDepartment of Chemistry, Ilam University, Ilam, IranJournal Article20140602The VO(IV) complexes of tridentate ONO Schiff base ligands derived from 2- aminobenzoicacid and salicylaldehyde derivatives were synthesized and characterized by IR, UV–Vis and elemental analysis. Electrochemical properties of the vanadyl complexes were investigated by cyclic voltammetry. A good linear correlation was observed between the oxidation potentials and the electron-withdrawing character of the substituents on the Schiff bases, showed the following trend: MeO < H < Br < NO2. The thermogravimetry (TG) and differential thermoanalysis (DTA) of the synthesized complexes were carried out in the range of 20–700 °C. All of the complexes decomposed in three steps. The thermal decomposition pathways were closely related to the nature of the Schiff base ligands and preceded via first-order kinetics. The structures of compounds were determined by ab initio calculations. The optimized molecular geometry was calculated at the B3LYP/6-31G(d) level. The results suggested that, in the complexes, V(IV) ion was in square-pyramid or TBP (trigonal bipyramidal) NO4 coordination geometry. Also the bond lengths and angles were studied and compared.Iranian Chemical SocietyInorganic Chemistry Research2538-18651120170701Multi-wall Carbon Nanotubes Supported Molybdenum Acetylacetonate: Efficient and Highly Reusable Catalysts for Oxidation of Sulfides with Tert-butyl Hydroperoxide21303324410.22036/icr.2016.33244ENMehdi AraghiDepartment of Chemistry, Saveh Branch, Islamic Azad University, Saveh, IranShaghayegh AghamohammadDepartment of Chemistry, Saveh Branch, Islamic Azad University, Saveh, IranJournal Article20140420In the present work, highly efficient oxidation of sulfides catalyzed by MoO2(acac)2 supported on multi-wall carbon nanotubes, MWCNTs, modified with 1,2-diaminobenzene (DAB) and 2-aminophenol (AP), at room temperature are reported. The effects of various parameters such as reaction time, solvent, catalyst amount, oxidant, etc, were studied. These heterogenized catalysts showed high activity in the oxidation of a variety of linear, cyclic and aromatic sulfides with tert-butyl hydroperoxide (TBHP) in 1,2-dichloroethane as solvent under mild conditions. In these systems sulfides have been selectively oxidized to the corresponding sulfoxides and sulfones with short reaction times and high yields. In the case of aromatic sulfides, sulfoxide was produced as major product and in the case of linear sulfides only sulfoxide was produced. The [MoO2(acac)@amines-MWCNT] catalysts are stable under the reaction conditions and While, the homogeneous MoO2(acac)2 cannot recovered even one time, the MWCNT supported catalysts can be filtered and reused several times without significant loss of their activity.Iranian Chemical SocietyInorganic Chemistry Research2538-18651120170701Ammonium Decatungstocerate(IV): An Efficient Catalyst for the Protection and Deprotection of Tetrahydropyranyl Ethers31393324510.22036/icr.2016.33245ENDavud KarimianDepartment of Chemistry, University of Isfahan, Isfahan 81746-73441, IranBahram YadollahiDepartment of Chemistry, University of Isfahan, Isfahan 81746-73441, IranValiollah MirkhaniDepartment of Chemistry, University of Isfahan, Isfahan 81746-73441, IranJournal Article20140427In multi-step organic syntheses, the protection and deprotection of tetrahydropyranyl (THP) ethers is one of the most frequently used methods. Over the years, different methods have been used from various catalytic systems for the protection of hydroxyl groups as THP ethers and their deprotection. Herein we have reported that various alcohols and phenols have been efficiently converted to the corresponding THP ethers in high to excellent yields using catalytic amounts of ammonium decatungstocerate(IV) at room temperature. In the presence of this catalyst, various THP ethers have also been deprotected to the parent alcoholic or phenolic compounds. Mild reaction conditions, high to excellent yields, easy handling, compatibility with the other protecting groups and heterogeneous, non-toxic and cost-effective catalyst are some of the major advantages of this procedure. Because of its operational simplicity, generality, and efficacy, this method could be used for the conversion of various hydroxyl compounds to the corresponding THP ethers and vice-versa.Iranian Chemical SocietyInorganic Chemistry Research2538-18651120170701Synthesis and Crystal Structures of Three New Hetero-binuclear Hg(II)-Cu(II) Schiff Base Complexes40493337510.22036/icr.2016.33375ENHadi KargarHadi Kargar
Assistant Prof. of Inorganic Chemistry
Department of Chemistry
Payame Noor University
Ardakan
I.R. of Iran
e-mail: h.kargar@pnu.ac.ir
Tel.: +98-352-7220011 ext. 157
Fax: +98-352-72281100000-0002-2817-0937Reza Kia*Chemistry Department, Sharif University of Technology, P.O. Box: 11155-3516 , Tehran, IranJournal Article20140513New hetero-binuclear Hg-Cu Schiff base complexes were prepared by reaction of 2,2'-[1,1'-(2,2-dimethylpropane-1,3-diyldinitrilo)-diethyldyne]diphenolato}copper(II) (CuL1) and 6,6'-X-2,2'-[(2,2-dimethylpropane-1,3-diyl)bis(nitrilomethanylylidene)]diphenolato copper(II) [(X = ethoxy (CuL2) and methoxy (CuL3)], with HgCl2 to give [Cu(L1)HgCl2] (1), [Cu(L2)HgCl2] (2), and [Cu(L3)HgCl2] (3), respectively. In the precursor Cu(II) complexes (CuL1-CuL3), the coordinated phenolic oxygen atoms and those of the substituents at 3,3'-positions (in 2 and 3) on aromatic ring can act as additional site of coordination to HgCl2 as metallo-ligand to make heterobinuclear Cu-Hg complexes. The H2L1, H2L2, and H2L3 Schiff base ligands were characterized by elemental analyses, 1H NMR and FT IR techniques. The related binuclear Cu-Hg complexes were characterized by elemental analyses and single-crystal X-ray diffraction. The main coordination sites for the HgCl2 unit are phenolic oxygen atoms and there are also short intramolecular Hg…O (methoxy, and ethoxy segments) contacts in 2 and 3. The crystal packing of 3 shows one-dimensional extended chains along the b-axis through pair of centro-symmetric C–H…Cl interactions. The new complexes crystallize in Pbca (1), P21/n (2), and P21/c (3) space groups. Iranian Chemical SocietyInorganic Chemistry Research2538-18651120170701Synthesis, Characterization and Antioxidant Activity of Two Novel Oxovanadium (IV) Curcuminoids50583337610.22036/icr.2016.33376ENKhosro MohammadiChemistry Department, Faculty of Sciences, Persian Gulf UniversityMansooreh ZahediChemistry Department, Faculty of Sciences, Persian Gulf University, Bushehr 75169, I.R. IranJournal Article20141018The reaction of bis[4-hydroxy-3-methoxyphenyl]-1,6-heptadiene-3,5-dione (curcumin) and two novel ligands of bis[4-tetrabenzylglucose-3-methoxyphenyl]-1,6-heptadiene-3,5-dione (bis(tetrabenzylglucose)curcumin) (BTBGC) and bis[4-tetraacetylglucose-3-methoxyphenyl]-1,6-heptadiene-3,5-dione (bis(tetraacetylglucose)curcumin) (BTAGC) with vanadium in methanol, in a 2:1 molar ratio, which yield the complexes of ML2 where M is [VO]2+, have been synthesized and characterized by FT-IR, mass spectrometry, 1H NMR spectroscopy and elemental analysis. These novel compounds were also examined for their antioxidant activity (using Trolox Equivalent Antioxidant Capacity (TEAC) antioxidant assay as a measure of their overall ability to scavenge free radicals compared to antioxidant standards such as Trolox); compounds with free hydroxyl groups were more active than those one whose locking such and also the metal complexes showed more activity than Trolox. The antioxidant capacity was decreased in BTBGC, BTAGC and their complexes compared to curcumin and its oxovanadium (IV) complex, corroborating the importance of curcumin’s free phenolic OH groups for scavenging oxidants potential. And also, the presence of the methoxy group increases the activity.Iranian Chemical SocietyInorganic Chemistry Research2538-18651120170701New Tetraaza Schiff Base Ligands and Their Complexes: Synthesis, Characterization and Thermodynamic Studies59683337710.22036/icr.2016.33377ENAlison ZamanpourDepartment of Chemistry, Islamic Azad University, Firouzabad Branch, Firouzabad, IranMozaffar AsadiChemistry Department, College of Sciences, Shiraz University, Shiraz 71454, I. R. IranGhodratollah AbsalanChemistry Department, College of Sciences, Shiraz University, Shiraz 71454, I. R. IranJournal Article20141023Some new symmetrical tetraaza Schiff base ligands containing 2-quinolinecarboxaldehyde moiety formed from condensation reaction of 2-quinolinecarboxaldehyde and o-phenylenediamine derivatives, such as N, Nˊ-bis(2-quinolylmethylidene)-4-methoxy-1, 2-phenylenediimine (L1), N, Nˊ-bis(2-quinolylmethylidene)-4-methy-1, 2-phenylenediimine (L2), N, Nˊ-bis(2-quinolylmethylidene)-4-chloro-1, 2-phenylenediimine (L3), N, Nˊ-bis(2-quinolylmethylidene)-4-carboxylic-1, 2-phenylenediimine (L4), N, Nˊ-bis(2-quinolylmethylidene)-4-nitro-1, 2-phenylenediimine (L5), and their Ni(II), Cu(II), Zn(II) complexes, have been synthesized. The ligands and their metal complexes have been characterized by molar conductance, elemental analysis, IR, 1H-NMR and UV-Vis spectroscopy. The formation constant and the free energy of the complexes were determined using electronic spectroscopic titration at constant ionic strength 0.1 M (NaClO4), at 25°C in MeOH solvent. The comparison of the formation constants and the thermodynamic parameters show that the trend of complex formation toward a given ligand is as follows: L2 > L1 > L3 > L5 > L4 . The trend for complex formation of the metal ions with a given ligand is as follows: Zn (II) > Cu (II) > Ni (II).Iranian Chemical SocietyInorganic Chemistry Research2538-18651120170701Synthesis, Characterization and X-Ray Crystal Structure of a Cobalt(III) Complex with 2-Bis(pyridine-2-carboxamido)-4,5-dimethylbenzene Ligand69783337810.22036/icr.2016.33378ENSoraia MeghdadiIsfahan University of TechnologyKurt MereiterVienna University of Technology, AustriaNarges Shams MohammadiIsfahan University of TechnologyAhmad AmiriDepartment of Chemistry, University of TehranJournal Article20141202An octahedral cobalt(III) complex, trans-[(Me2bpb)Co(bzlan)2]ClO4 (1), with H2Me2bpb = N,N’-(4,5-dimethyl-1,2-phenylene)dipicolinamide and bzlan = benzylamine, has been synthesized and characterized by elemental analyses, IR, UV-Vis, and 1H NMR spectroscopy. The structure of this complex has been determined by X-ray crystallography. The Me2bpb2– is a di-anionic tetradentate ligand furnishing a N4 set, such that two N atoms of the two pyridine rings and two amido N atoms occupy four equatorial positions. The two benzylamine ligands occupy the two axial positions leading to a distorted octahedral geometry around the central cobalt ion. The electrochemical behavior of this complex in acetonitrile solution indicates that the irreversible oxidation of 4,5-dimethylorthophenylene moiety and reduction of pyridine rings of the free ligand appear as reversible waves in the cyclic voltammogram of its cobalt(III) complex. Concomitant CoIII/CoII redox process and solvolysis in acetonitrile solution is observed. This irreversible redox process becomes reversible in the presence of excess benzylamine.Iranian Chemical SocietyInorganic Chemistry Research2538-18651120170701Synthesis of Zinc Dimethyldithiocarbamate by Reductive Disulfide Bond Cleavage of Tetramethylthiuram Disulfide in Presence of Zn2+79843337910.22036/icr.2016.33379ENMaryam BagheriDepartment of Chemistry, Isfahan University of TechnologyKurt MereiterFaculty of Chemistry, Vienna University of TechnologyJournal Article20150126The zinc(II) complex [Zn2(dmdtc)2(μ-dmdtc)2] has been synthesized directly from thiram ligand, containing a disulfide bond {dmdtc = N,N-dimethyldithiocarbamate; thiram = N,N-tetramethylthiuram disulfide}, and characterized by elemental analysis and spectroscopic methods. Surprisingly thiram, undergoes a reductive disulfide bond scission upon reaction with Zn2+ in methanolic media to give the [Zn2(dmdtc)2(μ-dmdtc)2] complex. The crystal structure of Zn(II) complex has been determined by single crystal X-ray diffraction. Zinc is 4+1 coordinate, with four nearly identical tetrahedral bonds and a longer fifth bond being similar to some reported [Zn(dtc)2(L)] complexes. The crystal structure of this complex is built up of dimeric units, [Zn(dmdtc)(μ-dmdtc)2], so that each unit has two thiocarbamate groups, one wholly bound to a zinc atom as a bidentate ligand and the other in a bridging coordination mode between the two Zn(II) atoms. This structure clearly shows scission of the disulfide bond in the thiram ligand to give two dimethyldithiocarbamate ligands coordinated to the Zn(II) ion.