Phyto-Assisted Synthesis and Characterization of Ta2O5 Nanoparticles and Their Theoretical and Electrochemical Studies

Double condensation of 2-acetylpyridine with 1,3-diaminobenzene-4,6-dicarboxaldehyde affords 2,7-bis(2-pyridyl)-1,8-diazaanthracene, which was subsequently oxidized to the corresponding quinone. Electrochemical studies indicate two reversible reduction processes corresponding to semiquinone and hydroquinonate formation. Electron-withdrawing pyridine groups and the nitrogen atoms make this somewhat more easily reduced than anthraquinone. This compound is redox-active and can be reduced to its radical anion, a potential spin-bearing ligand for the construction of [2 × 2] metallo-grid structures.Key words: quinone, grid, supramolecular, bistridentate, electrochemistry, metallosupramolecular chemistry.

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The synthesis and characterization of the pendant-armed ligand N,N′-bis(2′-pyridylmethyl)-1,7-dithia-4,11-diazacyclotetradecane (L4) and crystal structures of L4 and the copper(II) complex [Cu(L4)](ClO4)2 Crystal structure of the nickel(II) complex of N-(2′-pyridylmethyl)-1,4,7-trithia-11-azacyclotetradecane (L2), [Ni(L2)(CH3CN)](ClO4)2·CH3CN

Canadian Journal of Chemistry ◽

10.1139/v05-241 ◽

2006 ◽

Vol 84 (2) ◽

pp. 187-195 ◽

Cited By ~ 9

Author(s):

B CM Chak ◽

A McAuley

Keyword(s):

Crystal Structure ◽

Copper Ion ◽

Esr Spectra ◽

Synthesis And Characterization ◽

Electrochemical Studies ◽

High Dilution ◽

Donor Ligand ◽

X Ray ◽

Distorted Octahedral

The synthesis and characterization of the mixed donor ligand N,N′-bis(2′-pyridylmethyl)-1,7-dithia-4,11-diazacyclotetradecane (L4) containing two pendant pyridine arms is described. The macrocycle formation involves reaction of N-tosylbis(2-bromoethyl)amine with N-tosylbis(3-mercaptopropyl)amine at high dilution followed by detosylation at the nitrogen atoms using LiAlH4 in view of the presence of the thioether groups. An X-ray study of the ligand shows the sulphur atoms lie exo to the macrocyclic ring. The nickel(II) and copper(II) complexes of L4 have been characterized and the X-ray structure of the Cu(II) ion exhibits a five-coordinate copper ion despite the presence of six available donor atoms. In the case of ligand N-(2-pyridylmethyl)-1,4,7-trithia-11-azacyclotetradecane (L2), with a single pendant N donor, the Ni(II) complex is distorted octahedral with a molecule of acetonitrile in the sixth site. Details of UVvis, ESR spectra, and electrochemical studies on the complexes are presented.Key words: synthesis, pendant-armed, mixed donor S,N macrocycles, copper, nickel.

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Intramolecular photoinduced electron transfer in cobalt(II) chlathrochelate-zinc porphyrin assemblies leading to long-lived Co(I) species

Journal of Porphyrins and Phthalocyanines ◽

10.1142/s1088424614500965 ◽

2014 ◽

Vol 18 (12) ◽

pp. 1125-1130 ◽

Cited By ~ 6

Author(s):

Sanae El Ghachtouli ◽

Régis Guillot ◽

Winfried Leibl ◽

Ally Aukauloo

Keyword(s):

Electron Transfer ◽

Photoinduced Electron Transfer ◽

Synthesis And Characterization ◽

Electrochemical Studies ◽

Charge Accumulation ◽

Zinc Porphyrin ◽

X Ray ◽

Induced Charge ◽

Cobalt Center

We report herein the synthesis and characterization of novel cobalt chlathrochelate-zinc porphyrin assemblies. X-ray data and electrochemical studies support the formation and maintenance of these structures both in solid and solution states. Light induced charge accumulation at the cobalt center was realized in the presence of a sacrificial electron donor. The photogenerated Co(I) species was stable in the ms time scale in aqueous medium.

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Synthesis and characterization of dendritic platinum bisferrocenylacetylide complexes

Canadian Journal of Chemistry ◽

10.1139/v11-159 ◽

2012 ◽

Vol 90 (3) ◽

pp. 278-289

Author(s):

Qing Han ◽

Li-Jun Chen ◽

Hai-Bo Yang ◽

Quan-Jie Li ◽

Jiuming He ◽

...

Keyword(s):

Mass Spectrometry ◽

Diffusion Coefficient ◽

Coupling Reaction ◽

Synthesis And Characterization ◽

Electrochemical Studies ◽

Maldi Tof Ms ◽

Electrochemically Active ◽

Key Steps ◽

Tof Ms

A series of new dendritic platinum bisferrocenylacetylide complexes have been synthesized utilizing the coupling reaction of trans-Pt complexes with C–H bonds in alkynes as key steps. These new bimetallic dendrimers were fully characterized by multinuclear NMR (1H, 13C, and 31P) and mass spectrometry (MALDI-TOF-MS and CSI-TOF-MS). Electrochemical studies of these complexes were carried out and revealed that all of the redox moieties are stable, independent, and electrochemically active. In addition, all metallodendrimers show one-electron reaction responses, and the increased sizes of these complexes did not exhibit a dramatic influence on the diffusion coefficient.

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Spectroscopic and Electrochemical Studies on Oxaporphyrins and Oxathiaporphyrins

Journal of Porphyrins and Phthalocyanines ◽

10.1002/(sici)1099-1409(199801/02)2:1<69::aid-jpp55>3.0.co;2-1 ◽

1998 ◽

Vol 02 (01) ◽

pp. 69-78 ◽

Cited By ~ 34

Author(s):

B. SRIDEVI ◽

S. JEYAPRAKASH NARAYANAN ◽

A. SRINIVASAN ◽

M. V. REDDY ◽

T. K. CHANDRASHEKAR

Keyword(s):

Excited States ◽

Electrochemical Behaviour ◽

Resonance Interaction ◽

Sharp Contrast ◽

Synthesis And Characterization ◽

Emission Characteristics ◽

Electrochemical Studies ◽

Reduction Potentials

The synthesis and characterization of oxaporphyrins ( OTPP and O 2 TPP ) containing one and two furan rings in place of pyrrole and a mixed oxathiaporphyrin ( OSTPP ) is reported. Spectroscopic and electrochemical studies reveal that oxaporphyrins exhibit optical and emission characteristics closer to the parent H 2 TPP , while their electrochemical behaviour parallels that reported for mono and dithiaporphyrins. However the characteristics of the mixed oxathia derivative resemble that of monothiaporphyrin. Protonation studies reveal weaker resonance interaction between the β-hydrogens and meso-phenyl substituents in sharp contrast to thiaporphyrins. The reduction potentials for OSTPP and O 2 TPP indicate stabilization and destabilization of their LUMOs relative to the parent H 2 TPP in the ground and excited states, respectively.

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