XIV
h
International Conference on Molecular Spectroscopy, Białka Tatrzańska 2017
144
T1: P–11
From basic photophysics to the development of new chromophores:
evaluation of photochromism and possible ESIPT and charge transfer
in hydroxycoumarin-based compounds
Agnieszka Jamrozik
1
, Joanna Buczyńska
1
, Barbara Leśniewska
1
,
Ding-Yah Yang
2
, and Jacek Waluk
1
1
Department of Photochemistry and Spectroscopy, Institute of Physical Chemistry, Polish Academy
of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland, e-mail: ajamrozik@ichf.edu.pl
2
Department of Chemistry, Tunghai University, 181, Taichung-Kang Rd. Sec.3, Taichung 407,
Taiwan
Large series of new, hydroxycoumarin-based compounds were found to exhibit complex
photochromic properties. For most of the compounds, we observed changes of the solution
colour upon UV irradiation. The electronic absorption and emission spectra were monitored as a
function of irradiation time in solvents of different polarities. These experiments revealed a
presence of several species exhibiting not only photochromism, but also thermochromic
behaviour. It might indicate such processes as creation of various tautomeric forms as a result of
excited-state intramolecular proton transfer (ESIPT), rotations of specific moieties, as well as
charge transfer phenomena, possible in compounds bearing the dimethylamine group.
Photochromic behaviour was also observed in the solid state and investigated by X-ray
diffractometry and vibrational spectroscopy techniques combined with quantum chemical
calculations. We hope these studies can explain the very complicated photochromism and
thermochromism, which might be important not only for theoretical photophysics, but also for
potential applications of the investigated compounds as new photochromic colorants or sensors.
Fig. 1. Colour changes of C21H14BrNO3S upon UV irradiation: in solution (A) and in solid phase (B).
Keywords: coumarins; photochromism; fluorescence
References
[1] Pei-Yu Kuo, Rong-Ren Chuang, Ding-Yah Yang, Mol Divers 13 (2009) 253.
XIV
h
International Conference on Molecular Spectroscopy, Białka Tatrzańska 2017
145
T1: P–12
Spectroscopic and structural properties of oxatruxene
Barbara Leśniewska
1
, Krzysztof Górski
1
, Justyna Mech-Piskorz
1
,
Krzysztof Noworyta
1
, and Marek Pietraszkiewicz
1
1
Institute of Physical Chemistry Polish Academy of Sciences; Kasprzaka 44/52, 01-224 Warsaw,
Poland, e-mail: blesniewska@ichf.edu.pl
We present structure and properties of a new compound called 5-oxatruxene (Fig. 1b) which
may have great potential in optoelectronic devices and in organic photovoltaics. The changes in
physical properties of the molecule are observed as a result of introduction of oxygen atom into
the truxene system (Fig. 1a). The most significant changes are seen in the photophysical
properties, i.e., the increase of the fluorescence quantum yield from 9 to 37% and the
appearance of low energy bands. Moreover, the absorption spectrum of 5-oxatruxene in solution
is nearly constant in the region 268–303 nm, with the average molar absorption coefficient
around 30000 dm
3
·mol
–1
·cm
–1
.This property of the presented molecule and some of its
derivatives makes them very valuable in UV light-harvesting technologies or as UV filters.
O
a)
b)
Fig. 1. Structure of hexaethyltruxene (a) and 5-oxatruxene (b).
Keywords: truxene; oxatruxene; emission; quantum yield; spectroscopy
XIV
h
International Conference on Molecular Spectroscopy, Białka Tatrzańska 2017
146
T1: P–13
Spectroscopic studies on binuclear complex of neodymium(III) ions
with N phenylanthranilic acid
Lidia Zapała
1
, Małgorzata Kosińska
1
, Jan Kalembkiewicz
1
,
Urszula Maciołek
1
, and Anna Kuźniar
1
1
Department of Inorganic and Analytical Chemistry, Faculty of Chemistry, Rzeszow University of
Technology, Al. Powstańców Warszawy 6, 35-959 Rzeszów, Poland, e-mail: mkosinska@prz.edu.pl
N-Phenylanthranilic acid (Fig. 1) belongs to fenamates: N-substituted anthranilic acid
derivatives. The most known fenamates (mefenamic acid, tolfenamic acid, meclofenamic acid)
are used clinically as nonsteroidal anti-inflammatory drugs (NSAIDs) for the treatment of fever,
pain, and inflammation. N-Phenylanthranilic acid was established as the minimum structural
requirement for achievement the biological properties of fenamates [1]. It is widely used in
medicine, pharmacy and analytical chemistry as starting material for synthesis of
pharmaceutically important molecules such as antimalarials, anti-inflammatory and
antineoplastics, comparative medical research and for metal ion determination [2].
Fig. 1. The molecular structure of N-phenylanthranilic acid.
N-Phenylantranilic acid and its derivatives have attracted attention, because of their
complexing properties. In the literature there is only several studies on lanthanide complexes
with fenamate ligands. Until now descriptions of binary and ternary mononuclear lanthanide
complexes with N-phenylanthranilic acid and 1,10 phenanthroline can be found, but there are no
data about binuclear lanthanide complexes with N phenylanthranilic.
Therefore, in this work new binuclear complex of Nd(III) ions with N-phenylanthranilic acid of
molecular formula Nd
2
(nfa)
5
(OH)·4H
2
O (where nfa = C
13
H
11
NO
2
) was synthesized and
characterized by elemental analysis, infrared spectroscopy, ultraviolet spectra, XRD and coupled
TG–FTIR–MS techniques.
The X ray powder diffraction patterns of the studied compound revealed that it has
crystalline structure. The IR spectra provided the information about coordination mode of the
organic ligands in obtained complex. It was concluded that the carboxylate group of N-
phenylanthranilic acid is involved in coordination of Nd(III) ions in the bidentate mode and
coordination does not occur through the nitrogen atom.
The TG–FTIR–MS technique was employed to study a decomposition pathway of the
obtained complex. The data allowed for the identification and comparison of gaseous products
evolved during pyrolysis and oxidative decomposition of the considered compounds. The
influence of the atmosphere (air or nitrogen) on the mechanism of thermal decomposition was
confirmed. It was stated, that in nitrogen atmosphere the gaseous products of thermal
decomposition contained mainly H
2
O, CO, CO
2
, diphenylamine and the fragments from partial
decomposition of organic ligands. On the other hand, H
2
O, CO, CO
2
, NO, ammonia as well as
fragments from partial decomposition of organic ligands was identified in air atmosphere.
Keywords: neodymium; N-phenylanthranilic acid; complex; spectral studies
References
[1] P. Garg, M.C. Sanguinetti, Molecular Pharmacology 82 (2012) 795.
[2] L. Zapała, J. Kalembkiewicz, Talanta 69 (2006) 601.
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