65639-43-2Relevant academic research and scientific papers
Synthesis, X-ray crystallography, thermogravimetric analysis and spectroscopic characterization of isostructural one-dimensional coordination polymers as sorbents for some anions
Ghanbari, Bahram,Shahhoseini, Leila,Owczarzak, Agata,Kubicki, Maciej,Kia, Reza,Raithby, Paul R.
, p. 1783 - 1796 (2018/04/03)
A new diaza-macrocyclic ligand bearing two pyridine side arms (L2) was synthesized and characterized by single-crystal X-ray diffraction (SCXRD), elemental analysis, FT-IR, and 1H and 13C NMR methods. The macrocyclic ligand showed a great tendency to act as an appropriate tecton in the formation of coordination polymers in the presence of Cu, Ni, Mn, Pb, and Cd chlorides. Five new isostructural one dimensional metal-organic coordination polymers [{M(Cl)2}(L)4] (M = Cu, Ni, Mn, Pb, Cd) were prepared in DMSO or DMF and characterized by elemental analysis, IR spectroscopy, TGA-DTG, powder X-ray diffraction (PXRD) and single-crystal X-ray diffraction. All of the polymers were employed as solid sorbents for Cr(vi) anions in aqueous solution. Within the series, the Pb(ii) coordination polymer demonstrated notable absorption behavior for sorption of Cr(vi) and some oxo-anions such as MoO42-, WO42-, and MnO4- (environmental concern anions), together with HPO42-. The anion adsorption properties were attributed to the presence of surface positive charge on the coordination polymer.
Through-space electronic communication of zinc phthalocyanine with substituted [60]Fullerene bearing O2Nxaza-crown macrocyclic ligands
Ghanbari, Bahram,Shahhoseini, Leila,Mahlooji, Niloofar,Gholamnezhad, Parisa,Taheri Rizi, Zahra
, p. 330 - 339 (2016/08/30)
Two new macrocyclic ligands containing 17- and 19-membered O2N3-donor aza-crowns anchored to [60]Fullerene were synthesized and characterized by employing HPLC, electrospray ionization mass (ESI-MS), 1H and 13C NMR, UV–vis, IR spectroscopies, as well as powder X-ray diffraction (PXRD) and thermogravimetric analysis (TGA) in solid state. TGA measurements revealed that upon linking each of these macrocycle rings to [60]Fullerene, the decomposition point measured for [60]Fullerene moiety was increased, indicating on the promoted stability of [60]Fullerene backbone during binding to these macrocyclic ligands. Moreover, the ground state non-covalent interactions of [60]Fullerene derivatives of O2Nx (x?=?2, and 3) aza-crown macrocyclic ligands namely, L1–L4 with zinc phthalocyanine (ZnPc) were also investigated by UV–vis absorption, steady state and time resolved fluorescence spectrophotometry in N-methyl-2-pyrrolidone (NMP). The calculation of Stern-Volmer constants (KSV) indicated on existence of an efficient quenching mechanism comprising of the excited singlet state of ZnPc in the presence of L1–L4. The observation of an appropriate correlation between decrease in fluorescence intensity and lifetime parameters led us to propose the occurrence of a static mechanism for the fluorescence quenching of ZnPc in the presence of L1–L3. The binding constants (KBH) of L1–L4/ZnPc were also determined applying the fluorescence quenching experiments. Meanwhile, the incompatibility of both KSV and KBH values found for L4 was also described in terms of structural features using DFT calculations using the B3LYP functional and 6-31G* basis set.
Spectroscopic studies of the complexation of iodine with 5,6,14,15-dibenzo-1,4-dioxa-8,12-diazacyclopentadeca-5,14-diene
Sadeghi,Shamsipur,Elahi
, p. 1594 - 1602 (2007/10/03)
The complex formation between iodine and 5,6,14,15-dibenzo-1,4-dioxa-8,12-diazacyclopentadeca-5,14-diene (DBDA 15C4) has been studied spectrophotometrically in chloroform solution. The resulting charge transfer complexes characterized by microchemical analysis and IR spectroscopy are formulated as [(DBDA 15C4)2I+]I3- and [(DBDA 15C4)2I+]I-. The rate constant and stability constant for the formation of [(DBDA15C4)2I+]I3- were calculated as k = (2.71 ± 0.04) × 102 min-1 and 5.25 ± 0.05 M-1, respectively. The complex shows semiconducting properties. The activation energy was evaluated as 0.88 eV.
Cyclic ligand control of kinetic lability. Kinetics of dissociation of nickel(II) complexes of a series of O2N2-donor macrocycles in acid
Ekstrom,Lindoy, Leonard F.,Smith, Roland J.
, p. 724 - 727 (2008/10/08)
The kinetics of dissociation in acid of a range of nickel complexes of 14-17-membered macrocycles containing an O2N2-donor set has been studied. Macrocycle structure was found to strongly influence the observed first-order dissociation rate constants, and, for the unsubstituted macrocycles, the kinetic labilities follow the ring size sequence 14 > 15 > 16 a number of other ions has also been studied.
