Oxygen Abstraction Reactions of N-Substituted Hydroxamic Acids with Molybdenum(V) and Vanadium(III) and -(IV) Compounds

Brown, D. A.; Bögge, Hartmut; Coogan, Raymond A.; Doocey, D.J.; Kemp, Terence J.; Müller, Achim; Neumann, Beate

doi:10.1021/ic950819r

Cited by 35 publications

(21 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…4 In spite of their possible biological importance, molybdenum-hydroxamate based siderophore systems have not been studied extensively. [5][6][7][8][9][10][11] Very strong interaction between desferrioxamine B (DFB = H 4 L ϩ ) and Mo() in acidic solution was shown by our previous pH-potentiometric and UV-VIS investigations. 7 Equimolar amount of DFB hinders the formation of polyoxomolybdates completely and a metal complex [MoO 2 (H 2 L)] ϩ is formed in which DFB is coordinated to a dioxomolybdenum core (MoO 2 2ϩ ) via its two hydroxamate chelates while its noncoordinated hydroxamic plus terminal amino groups are still protonated.…”

Section: Introductionmentioning

confidence: 99%

New insights into the solution equilibrium of molybdenum(vi)–hydroxamate systems: 1H and 17O NMR spectroscopic study of Mo(vi)–desferrioxamine B and Mo(vi)–monohydroxamic acid systems

2003

View full text Add to dashboard Cite

To complement our previous pH-potentiometric and spectrophotometric investigations, in the present work 17 O NMR studies on Mo()-desferrioxamine B (DFB) and Mo()-acetohydroxamic acid (Aha) systems, and 1 H NMR on Mo()-Aha, Mo()-benzohydroxamic acid (Bha) and -N-methylacetohydroxamic acid (MeAha) have been performed. Complete equilibrium models for all the studied systems are presented in this paper. Formation of a hydrogen bond could be suggested between the hydroxamate-NH of the coordinated primary monohydroxamic acids and oxo ligands of molybdenum under acidic conditions and, at ca. neutral pH, deprotonation of that NH was found. This is the first time that this process in a Mo()-hydroxamic acid system has been detected. The hydroximato chelate formed in this manner is unusually stable, and able to compete with hydrolytic processes up to basic pH, which results in the surprising fact that the interaction between Mo() and the small primary molecules, Aha and Bha exists up to much higher pH than between Mo() and the known powerful tris-chelator natural compound, DFB. Experimental ChemicalsThe molybdenum() stock solution was prepared from Na 2 -MoO 4 (Reanal). Acetohydroxamic acid and benzohydroxamic Scheme 1

show abstract

Section: Introductionmentioning

confidence: 99%

New insights into the solution equilibrium of molybdenum(vi)–hydroxamate systems: 1H and 17O NMR spectroscopic study of Mo(vi)–desferrioxamine B and Mo(vi)–monohydroxamic acid systems

2003

View full text Add to dashboard Cite

show abstract

“…Farkas et al, 2001) Oxidation of trivalent Ce to Ce(IV) was also suggested during mobilization of REY, during fluid-rock interaction, or during precipitation of chemical sediments in the presence of DFOB (Bau et al, 2013;Kraemer et al, 2017Kraemer et al, , 2015b. DFOB is a hydroxamate siderophore which contains three hydroxamate functional groups and past studies indicated that hydroxamate acids are also able to oxidize other redox-sensitive elements like Mo and V (Brown et al, 1996), Rh (Das et al, 2002) and U (Smith and Raymond, 1979).…”

Section: Chromium Mobilization and Isotope Fractionation In Presence mentioning

confidence: 99%

Mobilization and isotope fractionation of chromium during water-rock interaction in presence of siderophores

Kraemer

Viehmann

Bau

2019

Applied Geochemistry

View full text Add to dashboard Cite

Chromium mobilization and isotope fractionation during water-rock interaction in presence of the biogenic siderophore desferrioxamine B (DFOB) was studied with batch leaching experiments on chromitite and other igneous oxide and silicate rocks. Siderophores are a group of organic ligands synthesized and excreted by bacteria, fungi and plants to enhance the bioavailability of key nutrients like Fe. However, the DFOB siderophore also has a strong affinity for complexation with other metals such as Cr, U and rare earth elements. Here we show that leaching of rocks in the presence of the hydroxamate siderophore DFOB significantly increased the mobilization of Cr from all investigated rocks and caused an enrichment of the heavier 53 Cr isotope in leachates from chromitite (δ 53 Cr leach = +0.15 ± 0.087‰ to +2.14 ± 0.042 ‰) and from altered silicate rock (δ 53 Cr leach = +0.48 ± 0.07‰). In contrast, stable isotope fractionation of Cr was not observed in DFOB leachates of pristine silicate and low-Cr oxide rocks. Leaching in the presence of citric acid significantly enhanced Cr mobility, but did not result in fractionation of Cr isotopes. Chromium isotope fractionation is used in geochemistry as a quantitative proxy for oxidative weathering, because Cr(III) is oxidized *Revised manuscript with no changes marked to Cr(VI) in presence of MnO 2 and the associated Cr isotope fractionation is commonly linked to the presence of oxygen in the atmosphere. Our findings indicate that the presence of specific biogenic ligands with a high affinity for Cr are also able to fractionate Cr isotopes. The presence of biomolecules like siderophores during weathering, hydrothermal alteration or during mineral precipitation, therefore, may put constraints on the applicability of certain trace metals and their isotopes as redox proxies in modern and past environments. The results of our study also suggest that siderophores may have a high potential for (bio)remediation of Cr-contaminated sites and detoxification of contaminated natural waters. 1. Introduction Chromium occurs as Cr(III) and Cr(VI) redox species in the natural environment. While the former is rather immobile and non-toxic, the latter is mobile and considered toxic (Fendorf, 1995). Under present-day atmospheric conditions, Cr(VI) is the thermodynamically most stable redox species of Cr and, hence, Cr mobility is significantly increased during oxidative weathering. The mobile anionic species are chromate, CrO 4 2-, and bichromate, HCrO 4-. The aqueous Cr(VI) species solubilised during weathering enters streams, rivers, and ultimately the ocean (Oze et al., 2007). Chromium is used in a variety of technological applications such as electroplating, dyeing and tanning, and as such, significant quantities are introduced into the environment as a contaminant. The mobile form, Cr(VI), is considered carcinogenic (Kortenkamp et al., 1996) and its input into groundwater and surface water may have serious effects on flora and fauna. Hence, the remediation of Cr-contaminated soils and natur...

show abstract

“…3 ] þ species have been observed for these complexes [19]. For (catecholato) bis(-diketonato) vanadium(IV) complexes, reaction in the gas phase produces [V(acac) 3 ] þ and [V(bzac) 3 ] þ fragments as a result of cluster formation by moleculeion reactions characteristic of metal -diketonates [36][37][38]. …”

Section: Mass Spectramentioning

confidence: 99%

Synthesis, characterization, electrochemical study, and antimicrobial activity of bis(benzoylacetonato) vanadium(IV) complexes of biphenylphenols

Sharma

Thakur

Chaudhry

2010

Journal of Coordination Chemistry

View full text Add to dashboard Cite

New non-oxovanadium(IV) complexes of biphenylphenols, [VCl 2Àn (bzac) 2 (OAr 1,2 ) n ], have been synthesized in quantitative yields from the reaction of bis(benzoylacetonato) dichlorovanadium(IV) with the trimethylsilyl derivative of 2-and 4-phenylphenols in carbon tetrachloride. The complexes have been characterized by physicochemical, magnetic moment measurements, IR, mass spectra, and electrochemical studies. The thermal behavior of the complexes has been studied by TGA-DTA. The complexes have been screened for their antimicrobial activity against some pathogenic bacteria, Escherichia coli and Staphylococcus aureus and fungi, Candida albicans, Aspergillus niger, and Fusarium oxysporum, by two-fold serial dilution.

show abstract

Oxygen Abstraction Reactions of N-Substituted Hydroxamic Acids with Molybdenum(V) and Vanadium(III) and -(IV) Compounds

Cited by 35 publications

References 22 publications

New insights into the solution equilibrium of molybdenum(vi)–hydroxamate systems: 1H and 17O NMR spectroscopic study of Mo(vi)–desferrioxamine B and Mo(vi)–monohydroxamic acid systems

New insights into the solution equilibrium of molybdenum(vi)–hydroxamate systems: 1H and 17O NMR spectroscopic study of Mo(vi)–desferrioxamine B and Mo(vi)–monohydroxamic acid systems

Mobilization and isotope fractionation of chromium during water-rock interaction in presence of siderophores

Synthesis, characterization, electrochemical study, and antimicrobial activity of bis(benzoylacetonato) vanadium(IV) complexes of biphenylphenols

Contact Info

Product

Resources

About