Journal ArticleDOI
Kinetics And Mechanism Of Dissociation Of Some Bis-(N1-Substituted Biguanide) Complexes Of Nickel(II) In Aqueous Acid
TLDR
In this paper, the rates of dissociation of bis-(N1-methylbiguanide)nickel(II) and bis(N 1-phenylbiguanides)-nickel (II) in aqueous acid have been studied by the stopped-flow spectrophotmetric technique.Abstract:
The rates of dissociation of bis-(N1-methylbiguanide)nickel(II) and bis-(N 1-phenylbiguanide)nickel(II) in aqueous acid have been studies by the stopped-flow spectrophotmetric technique. The reactions occur in two consecutive steps, the first being faster than the second, ultimately forming the aquometal ion and the protonated ligand. For each step the rate is acid dependent as expressed by kx=k1 x[H+], where kx is the observed rate constant. The results are consistent with a mechanism involving an assisted dissociative process involving the protonated complexes with considerable solvent participation in the transition state. The observed lability order is Ni(PhbigH)2+ 2 > Ni(MebigH)2+ 2 > Ni(BigH)2+ 2.read more
Citations
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An EPR study of some copper(II) coordination compounds of substituted biguanides. Part IV
R.K. Ray,George B. Kauffman +1 more
TL;DR: In this paper, the authors measured the EPR and optical absorption spectra of some bis-copper(II) bases and their corresponding chloride salts in order to obtain information concerning the structure and nature of the bonding between the central metal atom and the ligands.
Journal ArticleDOI
Metal-mediated addition of alcohols to dicyandiamide
TL;DR: In this article, the synthesis of 1-amidino-O-alkylurea sulfates and their corresponding copper(II) and nickel (II) complexes are described.
Journal ArticleDOI
Transition Metal Complexes with 8-Hydroxyquinoline and Kelex 100 in Micellar Systems. Stoichiometry of the Complexes and Kinetics of Dissociation in Acid Media
M. Ismael,C. Tondre +1 more
TL;DR: In this paper, the stochastic properties of 8-hydroxyquinoline (HQ) and its alkylated analogue (C11-HQ) derived from Kelex 100 were investigated in micellar solutions made of cetyltrimethylammonium bromide (CTAB), 1-butanol, and water.
Journal ArticleDOI
Kinetics and mechanism of formation and dissociation of copper(II) and nickel(II) complexes of the Schiff base bis(acetylacetone)ethylenediimine in aqueous-organic solvent media
TL;DR: In this article, the pseudo-first-order rate constant for the formation of the title complexes M(baen), i.e. ML, conforms to the equation 1/kobs=1/k+1/(kKo.s · TL), where TL stands for the total ligand concentration in the solution, Ko.
References
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Journal ArticleDOI
Complex Compounds of Biguanides and Guanylureas with Metallic Elements.
Journal ArticleDOI
Kinetics and mechanism of dissociation of some chelate complexes of cobalt(III) and chromium(III)
D. Banerjea,B. Chakravarty +1 more
TL;DR: In this article, the kinetics of dissociation in acid medium of the chelate complexes of cobalt and chromium(III) with biguanide n-hexylbiguanide and phenylbiguanaide have been investigated under comparable conditions and the changes were all followed spectrophotometrically at suitable wavelengths.
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Ultraviolet spectral studies on metal biguanide complexes
TL;DR: In this paper, an attempt has been made to explain the shift of the u.v. spectra on the basis of a new metal biguanide complex structure taking into account the delocalised π-electron system in the ligand.
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Kinetics and mechanism of dissociation of ethylenedibiguanidenickel(II) and copper(II) and of bisbiguanide-nickel(II) in acid
TL;DR: In this paper, the kinetics of dissociation of the ethylenedibiguanidenickel (II) and copper(II), [M(EndibigH2)]2+, where M = NiII or CuII, and bisbiguanide-nickel(II, [Ni(BigH)2]2+, complexes in acid media forming the aquo-metal ions and the protonated ligand as the ultimate products have been studied by the stopped-flow technique.