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21.
X-射线晶体结构分析表明,在90℃的水热条件下,N-(8-喹啉基)吡啶-3-酰胺在Cd2+的存在下发生醇解。醇解产物为8-氨基喹啉(HL1)和吡啶-3-羧乙酯(HL2),它们与Cd(Ⅱ)配位形成四方锥型化合物。该配合物为单斜晶系,空间群P21/c,a=18.1089(1)?,b=8.9986(1)?,c=19.3070(2)?,β=113.085(1 相似文献
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Qingli Hao Hoong‐Kun Fun Suchada Chantrapromma Ibrahim Abdul Razak Fangfang Jian Xujie Yang Lude Lu Xin Wang 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(6):717-718
The title coordination complex, [Ni(C14H14O2PS2)2(C12H8N2)] or [Ni(pMePh‐dtp)2(phen)] (phen is 1,10‐phenanthroline; dtp is diaryldithiophosphate), has a non‐crystallographic twofold axis of symmetry through the Ni atom and the phen moiety. Two O,O‐di‐p‐tolyldithiophosphate (dtp) ions act as bidentate ligands. The central metal atom is coordinated by four S atoms from two dtp groups and two N atoms from the phen ligand. The title compound displays distorted octahedral geometry around the central Ni atom. 相似文献
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Redox equilibria of iron oxides in aqueous-based magnetite dispersions: effect of pH and redox potential 总被引:1,自引:0,他引:1
The effect of pH and redox potential on the redox equilibria of iron oxides in aqueous-based magnetite dispersions was investigated. The ionic activities of each dissolved iron species in equilibrium with magnetite nanoparticles were determined and contoured within the Eh-pH framework of a composite stability diagram. Both standard redox potentials and equilibrium constants for all major iron oxide redox equilibria in magnetite dispersions were found to differ from values reported for noncolloidal systems. The "triple point" position of redox equilibrium among Fe(II) ions, magnetite, and hematite shifted to a higher standard redox potential and an equilibrium constant which was several orders of magnitude higher. The predominant area of magnetite stability was enlarged to cover a wider range of both pH and redox potentials as compared to that of a noncolloidal magnetite system. 相似文献
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Shyamaprosad Goswami Subrata Jana Rinku Chakrabarty Hoong-Kun Fun 《Supramolecular chemistry》2013,25(3):143-148
A guanidine-based fluorescent receptor has been synthesised to study its binding behaviour towards anions (F? , Cl? , Br? , I? and AcO? ). The two donor N–H bonds of the receptor do not point in the same direction; rather, one N–H bond is intramolecularly hydrogen-bonded with the carbonyl oxygen atom. The nature of the donor–acceptor (DA) arrangement induces moderate binding properties. The binding behaviour towards monocarboxylic acids (benzoic acid and phenylacetic acid) is also compared. The binding behaviour of receptor 1 towards the F? anion is higher among the anions studied, whereas in the case of monocarboxylic acid, the binding constant with phenylacetic acid is higher than benzoic acid. 相似文献
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Farzin Marandi Dr. Babak Mirtamizdoust Suchada Chantrapromma Hoong‐Kun Fun 《无机化学与普通化学杂志》2007,633(9):1329-1332
A 2D lead(II) coordination polymer [Pb2(phen)2(N3)3(ClO4)]n,( 1 ) containing 1,10‐phenanthroline (phen) and two different anions, has been synthesized and characterized by elemental analysis, IR and 1H NMR spectroscopy and X‐ray crystallography. The single‐crystal X‐ray data show two different kinds of Pb2+ ions with coordination numbers of eight, Pb1 = PbN6O2 and Pb2 = PbN8, with hemidirected and holodirected structures, respectively. The supramolecular features in 1 is negiotated through the weak but directional C‐H···O and C‐H···N interactions and aromatic π–π stacking interactions. 相似文献
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Ming-Liang Zhang Yu-Peng Tian Xuan-Jun Zhang Jie-Ying Wu Sheng-Yi Zhang Dong Wang Min-Hua Jiang Suchada Chantrapromm Hoong-Kun Fun 《Transition Metal Chemistry》2004,29(6):596-602
A new Schiff base ligand derived from S-benzyldithiocarbazate and 4-[N-hydroxy ethyl-N-(methyl)amino]benzaldehyde (HL, where H is a dissociable proton) and its NiII, CuII, ZnII and PdII complexes were prepared and fully characterized. The structures of HL and Ni(L)2 were determined by X-ray diffraction analysis, which revealed that the geometry of the NiII ion is square-planar with two equivalent Ni=N and Ni=S bonds, and that the two neighboring molecules in two layers have weak contact. The electronic spectra and solution fluorescence of the ligand and the complexes were studied, and the quantum yields of single-photon fluorescence for the compounds were determined. The compounds possess two-photon absorption (t.p.a.) character and the t.p.a. coefficient and t.p.a. cross-section were determined by the Z-scan technique. Especially, the Zn(L)2complex and the HL ligand exhibit intensive two-photon fluorescence (t.p.f.) at 800 nm laser pulses in the femtosecond regime. 相似文献