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Synthesis and spectroscopic properties of new bis-tetrazoles.

Pazik A, Skwierawska A - J Incl Phenom Macrocycl Chem (2012)

Bottom Line: Syntheses of N,N'-phenyltetrazole podands link with aliphatic chains containing oxygen, nitrogen and sulphur atoms, are described.The UV-Vis titrations were performed to estimate the stability constant values of the respective complexes with Cu(2+) ion.The structure of ligand 2 has been deduced by X-ray crystallography.

View Article: PubMed Central - PubMed

Affiliation: Department of Chemical Technology, Chemical Faculty, Gdansk University of Technology, 80-233 Gdańsk, Poland.

ABSTRACT
Syntheses of N,N'-phenyltetrazole podands link with aliphatic chains containing oxygen, nitrogen and sulphur atoms, are described. The complexing properties of these compounds towards metal cations (Fe(2+), Cu(2+), Zn(2+), Co(2+), Ni(2+)) were investigated by absorption and infrared spectroscopy. The UV-Vis titrations were performed to estimate the stability constant values of the respective complexes with Cu(2+) ion. Changes in UV-Vis absorption spectra and IR spectra of compound 6 under various concentrations of Cu(2+) ion in methanol suggest formation of very unstable complex. The structure of ligand 2 has been deduced by X-ray crystallography.

No MeSH data available.


Related in: MedlinePlus

The changes in UV–Vis spectra in the presence of metal chloride (tenfold excess) for compounds a1 (c = 2 × 10−5 mol dm−3); b2 (c = 2.5 × 10−5 mol dm−3); c 3 (c = 2 × 10−5 mol dm−3) d UV–Vis titration of 2 (c = 2.5 × 10−5 mol dm−3) with copper(II) chloride (c = 10−4 mol dm−3, titration step 0.01 ml) in methanol at 298 K
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Fig5: The changes in UV–Vis spectra in the presence of metal chloride (tenfold excess) for compounds a1 (c = 2 × 10−5 mol dm−3); b2 (c = 2.5 × 10−5 mol dm−3); c 3 (c = 2 × 10−5 mol dm−3) d UV–Vis titration of 2 (c = 2.5 × 10−5 mol dm−3) with copper(II) chloride (c = 10−4 mol dm−3, titration step 0.01 ml) in methanol at 298 K

Mentions: In spectroscopic studies chlorides were used in methanol solution. Any absorbance change in spectra of 1–7 was observed in case of Li+, Na+, K+, Sr2+, Mg2+, and Ca2+ chlorides. We expected ligands 1–3 response, because of the presence of oxygen atoms which are hard bases according to HSAB theory. In next experiments Fe2+, Co2+, Zn2+, Ni2+ and Cu2+ chlorides were used. Figure 5 presents spectral absorbance changes of 1–3 upon addition of tenfold access of an appropriate salt. Bis-tetrazoles exhibit increase of all maxima upon addition of ferrous(II) chloride. In the presence of copper(II) chloride diminishing of maximum at 210 nm is only observed for 1. Zinc(II) and nickel(II) chlorides do not influence on ligands absorbance. It is worth to note that only ligand 3 shows positive response to cobalt(II) chloride. In the spectrum all main absorption bands are strengthened. Further spectroscopic titration of compounds 1–3 with ferrous(II), copper(II) and cobalt(II) chlorides show continuous increase of the main bands that makes determination of complexation constants impossible. As an example ligand 2 titration with copper(II) solution is shown in the Fig. 5d.Fig. 5


Synthesis and spectroscopic properties of new bis-tetrazoles.

Pazik A, Skwierawska A - J Incl Phenom Macrocycl Chem (2012)

The changes in UV–Vis spectra in the presence of metal chloride (tenfold excess) for compounds a1 (c = 2 × 10−5 mol dm−3); b2 (c = 2.5 × 10−5 mol dm−3); c 3 (c = 2 × 10−5 mol dm−3) d UV–Vis titration of 2 (c = 2.5 × 10−5 mol dm−3) with copper(II) chloride (c = 10−4 mol dm−3, titration step 0.01 ml) in methanol at 298 K
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3824287&req=5

Fig5: The changes in UV–Vis spectra in the presence of metal chloride (tenfold excess) for compounds a1 (c = 2 × 10−5 mol dm−3); b2 (c = 2.5 × 10−5 mol dm−3); c 3 (c = 2 × 10−5 mol dm−3) d UV–Vis titration of 2 (c = 2.5 × 10−5 mol dm−3) with copper(II) chloride (c = 10−4 mol dm−3, titration step 0.01 ml) in methanol at 298 K
Mentions: In spectroscopic studies chlorides were used in methanol solution. Any absorbance change in spectra of 1–7 was observed in case of Li+, Na+, K+, Sr2+, Mg2+, and Ca2+ chlorides. We expected ligands 1–3 response, because of the presence of oxygen atoms which are hard bases according to HSAB theory. In next experiments Fe2+, Co2+, Zn2+, Ni2+ and Cu2+ chlorides were used. Figure 5 presents spectral absorbance changes of 1–3 upon addition of tenfold access of an appropriate salt. Bis-tetrazoles exhibit increase of all maxima upon addition of ferrous(II) chloride. In the presence of copper(II) chloride diminishing of maximum at 210 nm is only observed for 1. Zinc(II) and nickel(II) chlorides do not influence on ligands absorbance. It is worth to note that only ligand 3 shows positive response to cobalt(II) chloride. In the spectrum all main absorption bands are strengthened. Further spectroscopic titration of compounds 1–3 with ferrous(II), copper(II) and cobalt(II) chlorides show continuous increase of the main bands that makes determination of complexation constants impossible. As an example ligand 2 titration with copper(II) solution is shown in the Fig. 5d.Fig. 5

Bottom Line: Syntheses of N,N'-phenyltetrazole podands link with aliphatic chains containing oxygen, nitrogen and sulphur atoms, are described.The UV-Vis titrations were performed to estimate the stability constant values of the respective complexes with Cu(2+) ion.The structure of ligand 2 has been deduced by X-ray crystallography.

View Article: PubMed Central - PubMed

Affiliation: Department of Chemical Technology, Chemical Faculty, Gdansk University of Technology, 80-233 Gdańsk, Poland.

ABSTRACT
Syntheses of N,N'-phenyltetrazole podands link with aliphatic chains containing oxygen, nitrogen and sulphur atoms, are described. The complexing properties of these compounds towards metal cations (Fe(2+), Cu(2+), Zn(2+), Co(2+), Ni(2+)) were investigated by absorption and infrared spectroscopy. The UV-Vis titrations were performed to estimate the stability constant values of the respective complexes with Cu(2+) ion. Changes in UV-Vis absorption spectra and IR spectra of compound 6 under various concentrations of Cu(2+) ion in methanol suggest formation of very unstable complex. The structure of ligand 2 has been deduced by X-ray crystallography.

No MeSH data available.


Related in: MedlinePlus