Study of the interaction between oxovanadium(IV) and hydroxamic acids

P. Buglyó, Norbert Pótári

Research output: Contribution to journalArticle

7 Citations (Scopus)

Abstract

The interaction between oxovanadium(IV) and primary hydroxamic acids (aceto- (HAha), benzohydroxamic acid (HBha) or N-hydroxy-N′-[3-(N-hydroxy-carbamoyl)-propyl]-heptane-1,7-dicarboxamide (H2Diha)) as well as the corresponding N-methyl substituted hydroxamic acids (HMeAha, HMeBha, H2MeDiha) was studied by pH-potentiometric and pH-stat methods in aqueous solution. Stoichiometry and stability constants of the VO(IV) complexes formed in the pH range 2.0-5.0 were determined and the effect of the substituents on the C or N atoms of the hydroxamic group is discussed. The dihydroxamic acids are more effective oxovanadium(IV) binders than the monohydroxamic ones. Above pH = 4.5-5.0 (depending upon ligand excess), slow redox reaction was found in all the systems studied. During this process, beside the oxidation of VO(IV) to the appropriate V(V)-hydroxamate complex, formation of amides as reduction products was detected under anaerobic conditions. The same reaction can also take place when stirring sparingly soluble VOA2 type complexes (A: Bha or MeBha) in water in the absence of oxygen. The exact stoichiometry of the redox reaction was determined by pH-stat measurements and found to be 2VO(R 1CON(R2)O)2 + R1CON(R 2)OH + H2O = 2[VO2(R1CON(R 2)O)2]- + 2H+ + R 1CON(R2)H (R1: CH3, C 6H5; R2: H, CH3) for the monohydroxamates. The N-methyl hydroxamic acids tend to oxidise VO2+ significantly slower than the corresponding primary ones.

Original languageEnglish
Pages (from-to)837-845
Number of pages9
JournalPolyhedron
Volume24
Issue number7
DOIs
Publication statusPublished - May 12 2005

Fingerprint

Hydroxamic Acids
Redox reactions
Stoichiometry
acids
Acids
Heptanes
Oxidation-Reduction
interactions
stoichiometry
Amides
Binders
Oxygen
Ligands
Heptane
stirring
Atoms
Oxidation
heptanes
Water
amides

Keywords

  • Amide formation
  • Hydroxamic acids
  • Oxovanadium(IV) complexes
  • pH-potentiometry
  • Stability constants
  • Vanadium(V)

ASJC Scopus subject areas

  • Biochemistry
  • Inorganic Chemistry
  • Physical and Theoretical Chemistry
  • Materials Chemistry

Cite this

Study of the interaction between oxovanadium(IV) and hydroxamic acids. / Buglyó, P.; Pótári, Norbert.

In: Polyhedron, Vol. 24, No. 7, 12.05.2005, p. 837-845.

Research output: Contribution to journalArticle

Buglyó, P. ; Pótári, Norbert. / Study of the interaction between oxovanadium(IV) and hydroxamic acids. In: Polyhedron. 2005 ; Vol. 24, No. 7. pp. 837-845.
@article{e16d6fa572374d07a88bf53425b5f4ee,
title = "Study of the interaction between oxovanadium(IV) and hydroxamic acids",
abstract = "The interaction between oxovanadium(IV) and primary hydroxamic acids (aceto- (HAha), benzohydroxamic acid (HBha) or N-hydroxy-N′-[3-(N-hydroxy-carbamoyl)-propyl]-heptane-1,7-dicarboxamide (H2Diha)) as well as the corresponding N-methyl substituted hydroxamic acids (HMeAha, HMeBha, H2MeDiha) was studied by pH-potentiometric and pH-stat methods in aqueous solution. Stoichiometry and stability constants of the VO(IV) complexes formed in the pH range 2.0-5.0 were determined and the effect of the substituents on the C or N atoms of the hydroxamic group is discussed. The dihydroxamic acids are more effective oxovanadium(IV) binders than the monohydroxamic ones. Above pH = 4.5-5.0 (depending upon ligand excess), slow redox reaction was found in all the systems studied. During this process, beside the oxidation of VO(IV) to the appropriate V(V)-hydroxamate complex, formation of amides as reduction products was detected under anaerobic conditions. The same reaction can also take place when stirring sparingly soluble VOA2 type complexes (A: Bha or MeBha) in water in the absence of oxygen. The exact stoichiometry of the redox reaction was determined by pH-stat measurements and found to be 2VO(R 1CON(R2)O)2 + R1CON(R 2)OH + H2O = 2[VO2(R1CON(R 2)O)2]- + 2H+ + R 1CON(R2)H (R1: CH3, C 6H5; R2: H, CH3) for the monohydroxamates. The N-methyl hydroxamic acids tend to oxidise VO2+ significantly slower than the corresponding primary ones.",
keywords = "Amide formation, Hydroxamic acids, Oxovanadium(IV) complexes, pH-potentiometry, Stability constants, Vanadium(V)",
author = "P. Bugly{\'o} and Norbert P{\'o}t{\'a}ri",
year = "2005",
month = "5",
day = "12",
doi = "10.1016/j.poly.2005.03.007",
language = "English",
volume = "24",
pages = "837--845",
journal = "Polyhedron",
issn = "0277-5387",
publisher = "Elsevier Limited",
number = "7",

}

TY - JOUR

T1 - Study of the interaction between oxovanadium(IV) and hydroxamic acids

AU - Buglyó, P.

AU - Pótári, Norbert

PY - 2005/5/12

Y1 - 2005/5/12

N2 - The interaction between oxovanadium(IV) and primary hydroxamic acids (aceto- (HAha), benzohydroxamic acid (HBha) or N-hydroxy-N′-[3-(N-hydroxy-carbamoyl)-propyl]-heptane-1,7-dicarboxamide (H2Diha)) as well as the corresponding N-methyl substituted hydroxamic acids (HMeAha, HMeBha, H2MeDiha) was studied by pH-potentiometric and pH-stat methods in aqueous solution. Stoichiometry and stability constants of the VO(IV) complexes formed in the pH range 2.0-5.0 were determined and the effect of the substituents on the C or N atoms of the hydroxamic group is discussed. The dihydroxamic acids are more effective oxovanadium(IV) binders than the monohydroxamic ones. Above pH = 4.5-5.0 (depending upon ligand excess), slow redox reaction was found in all the systems studied. During this process, beside the oxidation of VO(IV) to the appropriate V(V)-hydroxamate complex, formation of amides as reduction products was detected under anaerobic conditions. The same reaction can also take place when stirring sparingly soluble VOA2 type complexes (A: Bha or MeBha) in water in the absence of oxygen. The exact stoichiometry of the redox reaction was determined by pH-stat measurements and found to be 2VO(R 1CON(R2)O)2 + R1CON(R 2)OH + H2O = 2[VO2(R1CON(R 2)O)2]- + 2H+ + R 1CON(R2)H (R1: CH3, C 6H5; R2: H, CH3) for the monohydroxamates. The N-methyl hydroxamic acids tend to oxidise VO2+ significantly slower than the corresponding primary ones.

AB - The interaction between oxovanadium(IV) and primary hydroxamic acids (aceto- (HAha), benzohydroxamic acid (HBha) or N-hydroxy-N′-[3-(N-hydroxy-carbamoyl)-propyl]-heptane-1,7-dicarboxamide (H2Diha)) as well as the corresponding N-methyl substituted hydroxamic acids (HMeAha, HMeBha, H2MeDiha) was studied by pH-potentiometric and pH-stat methods in aqueous solution. Stoichiometry and stability constants of the VO(IV) complexes formed in the pH range 2.0-5.0 were determined and the effect of the substituents on the C or N atoms of the hydroxamic group is discussed. The dihydroxamic acids are more effective oxovanadium(IV) binders than the monohydroxamic ones. Above pH = 4.5-5.0 (depending upon ligand excess), slow redox reaction was found in all the systems studied. During this process, beside the oxidation of VO(IV) to the appropriate V(V)-hydroxamate complex, formation of amides as reduction products was detected under anaerobic conditions. The same reaction can also take place when stirring sparingly soluble VOA2 type complexes (A: Bha or MeBha) in water in the absence of oxygen. The exact stoichiometry of the redox reaction was determined by pH-stat measurements and found to be 2VO(R 1CON(R2)O)2 + R1CON(R 2)OH + H2O = 2[VO2(R1CON(R 2)O)2]- + 2H+ + R 1CON(R2)H (R1: CH3, C 6H5; R2: H, CH3) for the monohydroxamates. The N-methyl hydroxamic acids tend to oxidise VO2+ significantly slower than the corresponding primary ones.

KW - Amide formation

KW - Hydroxamic acids

KW - Oxovanadium(IV) complexes

KW - pH-potentiometry

KW - Stability constants

KW - Vanadium(V)

UR - http://www.scopus.com/inward/record.url?scp=17744382164&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=17744382164&partnerID=8YFLogxK

U2 - 10.1016/j.poly.2005.03.007

DO - 10.1016/j.poly.2005.03.007

M3 - Article

VL - 24

SP - 837

EP - 845

JO - Polyhedron

JF - Polyhedron

SN - 0277-5387

IS - 7

ER -