A series of iminopyridine ligated Co(II) (1a–7a) and Ni(II) (1b–7b) complexes were synthesized. The structures of complexes 3a, 4a, 5a, 7a, 5b, and 6b were determined by X-ray crystallographic analyses. Complex 3a formed a chloro-bridged dimer, whereas 4a, 5a, and 7a, having a substituent (4a, 5a: CH3; 7a: Br) at the 6-position of pyridine, producing the solid structures with a single ligand co...

A set of robust molecular cobalt catalysts for the generation of hydrogen from water is reported. The cobalt complex supported by the parent pentadentate polypyridyl ligand PY5Me(2) features high stability and activity and 100% Faradaic efficiency for the electrocatalytic production of hydrogen from neutral water, with a turnover number reaching 5.5 × 10(4) mol of H(2) per mole of catalyst with...

The effect of two concentrations of cobalt (Co(2+)) on photosynthetic activity and antioxidative response in Lemna minor L. were assessed 24, 48 and 72h after the start of the exposure. Higher concentration of cobalt (1mM) induced growth inhibition while lower concentration (0.01mM) increased photosynthetic pigments content. Analysis of chlorophyll a fluorescence transients revealed high sensit...

The trinuclear title compound, [Co(3)(CH(3)COO)(4)(C(20)H(22)N(2)O(6))(2)]·2CH(2)Cl(2), contains mixed-valence cobalt ions in the following order Co(III)-Co(II)-Co(III) where all the three cobalt ions are hexa-coordinated. The central cobalt ion is situated on an inversion centre and is in an all-oxygen environment, coordinated by four phenolate O atoms and two O atoms from bridging acetate gro...

A simple and new simultaneous fourth derivative spectrophotometric method is proposed for the analysis of a two-component system containing cobalt(II) and nickel(II) without separation using 2-hydroxy-3-methoxy benzaldehyde thiosemicarbazone (HMBATSC) as a chromophoric reagent. The reagent reacts with cobalt(II) and nickel(II) at pH 6.0, forming soluble brown and yellow colored species, respect...

In an effort to obtain synthetic analogues of water-oxidizing complex (WOC) of photosystem II (PS II) of plant photosynthesis, a Schiff base manganese and a cobalt complex, employing Niten, a SALEN type ligand, have been prepared. Cyclic and square wave voltammetric measurements have been performed to assess their redox characteristics. Both complexes undergo several reduction processes in cath...

in this paper, macrocyclic cobalt(ii) complexes [col1](no3)2.4h2o (1) and [col2](no3)2.2h2o (2) have been synthesized from the reaction of dialdehydes 1,2-bis(2-formylphenyl)ethane and 1,3-bis(2-formylphenyl)propane, co(no3)2.6h2o and 1,2-cyclohexanediamine with molar ration 1:1:1 in methanole and characterized by elemental analyses and ft-ir spectroscopy. then used as precursors for preparatio...

An account on the synthesis of an unsymmetrically substituted cobalt phthalocyanine, 2-(4-carboxyphenoxy)-9,16,23-tri-tert-butyl-phthalocyaninato-cobalt(II) (complex 1) and its symmetric counterpart, 2,9,16,23-tetra-tert-butylphthalocyanine (II) 2) is provided in this work. The complexes reported were applied electrooxidation hydrazine with a glassy carbon electrode serving as support for elect...

Manganese(II), iron(II), cobalt(II), and copper(II) derivatives of two inherently chiral, Tris(bipyridyl) cages (L and L') of type [ML]-(PF(6))(2)(solvent)(n) and [FeL'](ClO(4))(2) are reported, where L is the hexa-tertiary butyl-substituted derivative of L'. These products were obtained by using the free cage and metal template procedures; the latter involved the reductive amination of the res...