XIV
h
International Conference on Molecular Spectroscopy, Białka Tatrzańska 2017
149
T1: P–16
Synthesis and spectroscopic characterization
of symmetrically functionalized dodecaphenyl-POSS
with sterically hindered alkylaromatics
Maria Owińska
1
, Jan Mrówka
1
, Bartosz Handke
1
,
Witold Jastrzębski
1
, and Piotr Suder
1
1
Faculty of Materials Science and Ceramics, AGH-University of Science and Technology,
Al. Mickiewicza 30, 30-059 Kraków, Poland, e-mail: owinska@agh.edu.pl
Polyhedral oligomeric silsesquioxanes (POSS) draw attention because of their high
symmetry, easy syntheses, thermal and chemical stability. These cage-like molecules possessing
conjugated fragments (e.g. polyaromatics) exhibit self-assembly phenomenon due to the
influence of π-π stacking effect [1].
Dodecaphenyl-POSS contains twelve phenyl groups prone to electrophilic substitution and
their iodination by ICl provides [p-I-PhSiO
3/2
]
12
in a very good yield and para selectivity [2]. In
the present work synthesis of functionalized dodecaphenyl-POSS substituted with 3,5-
dimethylphenyl groups (II) via Suzuki-Miyaura cross-coupling has been described. The reaction
between para dodecaiodophenylsilsesquioxane (I) and 3,5-dimethylphenylboronic acid has been
carried out in the presence of in situ generated catalyst from Pd
2
dba
3
(tris(dibenzylideneacetone)dipalladium(0)) and P(o-tol)3 (tri(o-tolylphosphine)) as well as silver
(I) oxide as a base, at ambient conditions (Scheme 1).
Scheme 1. Synthesis of 3,5-dimethylphenyl substituted dodecaphenyl-POSS (II)
Presence of newly introduced substituents has been confirmed by
1
H,
13
C and
29
Si NMR. The
final compound (II) as well as its precursor (I) have been measured by FT-IR spectroscopy and
the results compared with spectra from calculated model molecule. Additionally,
thermogravimetric analysis and small angle X-ray scattering measurements have been conducted
on the final product.
Keywords: POSS; Suzuki-Miyaura cross-coupling; FT-IR spectroscopy
References
[1] B. Handke, Ł. Klita, J. Nizioł, W. Jastrzębski, A. Adamczyk, J. Mol. Struct. 1065–1066 (2014) 248.
[2] M. Roll, M.Z. Asuncion, J. Kampf, R. Laine, ACS Nano 2(2) (2008) 320.
XIV
h
International Conference on Molecular Spectroscopy, Białka Tatrzańska 2017
150
T1: P–17
Synthesis and spectroscopic characteristics of new cobalt complexes
with sulfonic derivatives of quercetin
Urszula Maciołek
1
, Anna Kuźniar
1
, Ewaryst Mendyk
2
, Marek Drewniak
2
,
Krzysztof Skrzypiec
2
, Tadeusz Wójcicki
2
, Jan Kalembkiewicz
1
,
and Małgorzata Kosińska
1
1
Department of Inorganic and Analytical Chemistry, Faculty of Chemistry, Rzeszów University of
Technology, Al. Powstańców Warszawy 6, 35-959 Rzeszów, Poland, e-mail: umaciolek@prz.edu.pl
2
Analytical Laboratory, Faculty of Chemistry, Maria Curie-Skłodowska University, 3 M. Curie-
Skłodowska Sq., 20-031 Lublin, Poland
The ability of complexing metal ions is one of the most important, apart from commonly
known biological activity, attributes of flavonoids. The interest in the synthesis of new
complexing compounds of flavonoids with metal ions results from their potential applications in
various areas (dyeing, preservation and protection of work of art, chemical analysis, pharmacy
and cosmetology). However, particular attention is attracted by their biological activity.
Chelating ion metals through flavonoids often leads to obtaining compounds characterized by
stronger biological activity compared to the very ligand. And yet, a few factors limit the
application of flavonoids, i.e. toxicity and their non-solubility in water. The solution is to seek
for synthetic derivatives characterized by better solubility, keeping the activity of the parent
compound. In case of flavonoids, such promising compounds are sulfonic derivative [1–4].
In this paper the conditions and molecular structure of the new complex of Co (II) ions with
NaQSA (sodium salt of quercetin-5’-sulfonic acid, Fig. 1) were investigated. Complex
compounds of Co (II) ions with the molar concentration ratios of substrates cM:cL=1:3 and
cM:cL=3:1 and pH = 5,1 were synthesized from water solutions. The chemical composition of
these compounds was determined based on elemental analysis, WD XRF spectroscopy
(determination of metal content) and thermal analysis (water content measurement). It can be
claimed that, regardless of synthesis conditions, Co(II) ions with NaQSA form yellow
microcrystalline complexes of composition CoL
2
∙8H
2
O (where L = NaQSA).
Crystal morphology of complexes is visualized by means of optical and atomic force
microscope. The obtained and chemically characterized complexes will constitute the subject for
further study in potential biological activity.
O
O
OH
OH
O
H
OH
SO
3
Na
OH
1
2
3
4
5
6
7
8
1'
2'
3'
6'
5'
4'
A
C
B
Fig. 1. The molecular structure of NaQSA.
Keywords: flavonoids; sulfonic derivative of quercetin; cobalt complexes
References
[1] S. Selvaraj, V. Devashya, S. Sethuraman, U. M. Krishnan, Med. Res. Rev. 34 (2014) 677.
[2] W. Król, S. Dworniczak, G. Pietsz, Z. P. Czuba, M. Kunicka, M. Kopacz, D. Nowak, Acta Pol. Pharm.
59 (2002) 77.
[3] E. Woźnicka, A. Kuźniar, D. Nowak, E. Nykiel, M. Kopacz, J. Gruszecka, K. Golec, Acta Poloniae
Pharmaceutica 70 (2013) 567.
[4] E. Pieniążek, J. Kalembkiewicz, M. Dranka, E. Woźnicka, J. Inorg. Biochem. 141 (2014) 180.
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