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This article describes the synthesis, characterization, and biological activity of novel square-planar cationic platinum(II) complexes containing glucoconjugated triazole ligands and a comparison with the results obtained from the corresponding five-coordinate complexes bearing the same triazole ligands. Stability in solution, reactivity with DNA and small molecules of the new compounds were evaluated by NMR, fluorescence, and UV–vis absorption spectroscopy, together with their cytotoxic action against pairs of immortalized and tumorigenic cell lines. The results show that the square-planar species exhibit greater stability than the corresponding five-coordinate ones. Furthermore, although the square-planar complexes are less cytotoxic than the latter ones, they exhibit a certain selectivity. These results simultaneously demonstrate that overall stability is a fundamental prerequisite for preserving the performance of the agents and that coordinative saturation constitutes a point in favor of their biological action.

In this work, Pt(II) complexes of previously synthesized steroidal thiosemicarbazones were synthesized and characterized. The ligands and their metal complexes were studied by analytical and spectroscopic data (elemental analysis, IR, 1D NMR and 2D NMR, HSQC, HMBC, NOESY, COSY), the analysis of which enabled complete 1H and 13C assignments of each compound including E and Z isomers. All the synthesized ligands and complexes were screened for their cytotoxic and antimicrobial activity. The results demonstrate that new steroidal thiosemicarbazone complexes were significantly less cytotoxic than corresponding steroidal thiosemicarbazones. Also, complexes show lower antimicrobial activity than the standard drugs, similar to the activity of the starting thiosemicarbazones. Почевши од претходно синтетисаних стероидних тиосемикарбазона, у овом раду су синтетисани и окарактерисани комплекси платине(II). Лиганди и њихови метални комплекси проучавани су аналитичким и спектроскопским методама (елементална анализа, ИЦ, 1D NMR и 2D NMR, HSQC, HMBC, NOESY, COSY). Анализом добијених података омогућена је потпуна 1H и 13C асигнација свих једињења укључујући Е и Z изомере. За синтетисане лиганде, као и њихове комплексе испитивана је цитотоксична и антимикробна активност. Резултати указују на то да нови стероидни тиосемикарбазонски комплекси испољавају значајно нижу цитотоксичност од одговарајућих стероидних тиосемикарбазона. Поред тога, комплекси поседују антимикробну активност сличну активности полазних тиосемикарбазона, a нижу од стандардних лекова

2-s2.0-85053752370, A ditopic bridging ligand, N,N?-bis(pyridine)-1,6,7,12-tetrakis-(4-methoxyphenoxy)perylene diimide (1) was synthesized. Metallosupramolecular self-assembly of 1 with 2,2?:6?,2?-terpyridyl-platinum(II) and/or -palladium(II) complex ions afforded to new triads [(terpy)M(II)-(1)-M(II)(terpy)](NO3)4 where, M(II) = Pt(II) (2), and Pd(II) (3), respectively. These isolated triads 2 and 3 and also free ligand 1 were fully characterized by FT-IR, 1H NMR, 13C DEPT NMR, 1H-1H COSY NMR, MALDI TOF and HRMS (MALDI-TOF/TOF-MS) mass techniques and UV/Vis spectroscopy. DFT studies revealed that the molecular structure of 1 is highly distorted and deviated from the planarity by bulky methoxyphenyl groups at bay positions. The calculated HOMO and LUMO are located on the PDI core and phenyl groups, and the band gap was found to be 2.27, 2.23 and 2.24 eV in DMSO for 1, 2 and 3, respectively. The calculated UV/Vis spectra are in good agreement with those of experimental results. Electrochemical, in situ spectroelectrochemical and in situ electrocolorimetric measurements in solution suggested that redox processes of the compounds are accompanied by favourable electron transport properties with remarkably narrow HOMO-LUMO gaps and intense light absorption over the visible range. The association of usually reversible and fast electron transfer processes with the net colour changes in solution pointed out the applicability of the compounds as an electrochromic material. The electrochromic performance measurements with the films of the compounds on indium tin oxide glass provided additional support for their usability as a colour changing material in electrochromic devices. Surface morphologies of the films were characterized by scanning electron microscopy (SEM). The metal complexes of 1, especially the platinum(II) complex (2), behaved as a good neutral and cathodic colouring electrochromic material with fast response time, long-term stability, and long-term write erase efficiency. The photovoltaic performance of the compounds as electron acceptor material was investigated by varying their relative ratio in the bulk heterojunction solar cells. It was found that the photovoltaic conversion efficiency of the devices strongly depends on the blend ratio. The optimized performance for the devices was obtained with the P3HT:PDIs (weight ratio 1.0:1.5) blended films. For this blend ratio, the device showed a maximum conversion efficiency of 3.91%, 8.17% and 5.18% for 1, 2 and 3, respectively. The results obtained reveal that employing 2 as an acceptor material has great potential for the development of highly efficient nonfullerene bulk heterojunction photovoltaic devices. © 2018, Consejo Nacional de Investigaciones Científicas y Técnicas, CONICET: 214Z090 Türkiye Bilimler Akademisi, TÜBA, The authors are grateful to the Turkish Scientific and Technical Research Council for support of this project under the grant [TÜBİTAK-Project No: 214Z090]. We also thank for computer time on FenCluster provided by Ege University Faculty of Science and TUBITAK-ULAKBIM Truba Resources. Ali Rıza Özkaya also thanks Turkish Academy of Sciences for partial support to this work. The authors gratefully thank Prof. Dr Bekir SALIH at the Hacettepe University for the MALDI-TOF and HRMS analysis., The authors are grateful to the Turkish Scientific and Technical Research Council for support of this project under the grant [TÜBİTAK-Project No: 214Z090 ]. We also thank for computer time on FenCluster provided by Ege University Faculty of Science and TUBITAK-ULAKBIM Truba Resources. Ali Rıza Özkaya also thanks Turkish Academy of Sciences for partial support to this work. The authors gratefully thank Prof. Dr Bekir SALIH at the Hacettepe University for the MALDI-TOF and HRMS analysis.

Cette thèse porte sur la luminescence de composés plan-carrés de platine(II), palladium(II) et nickel(II) en phase solide. Une compréhension globale et quantitative de divers effets peu explorés en littérature influençant les propriétés de luminescence, telles que la variation du centre métallique, de la structure ou des interactions intermoléculaires, est visée en utilisant une approche expérimentale. Dans cette optique, les complexes choisis montrent une émission issue d’une même transition électronique d-d, soit du premier triplet excité vers le singulet fondamental. L’application de modèles permet d’étudier et de comparer la structure électronique de ces systèmes. Les spectres de luminescence de plusieurs complexes avec des ligands bidentates comportant les mêmes atomes liants, pour la plupart étant de la famille des dithiocarbamates, sont mesurés et comparés. La variation de pression et de température est utilisée afin de gagner de l’information quantitative sur les effets, permettant une étude plus complète qu’une analyse spécifique à une condition choisie. La structure est mesurée par diffraction des rayons X, permettant de relier les changements énergétiques mesurés par la spectroscopie de luminescence à la variation de structure. Les divers facteurs influencent l’énergie et la forme des spectres de luminescence, ressortant sous forme de tendances quantitatives. En comparant ces tendances entre les divers systèmes étudiés et en les corrélant aux modèles théoriques, une caractérisation globale des effets étudiés est réalisée. En choisissant les complexes étudiés, l’effet de la variation du centre métallique, de la structure et des interactions de type M…H-C sont caractérisés. À travers les divers exemples recensés, il est vu que la nature du métal affecte considérablement les spectres de luminescence, par exemple au niveau de l’intensité. Cependant, des comparaisons entre les métaux 3d, 4d et 5d sont rarement effectuées, vu l’intensité presque nulle des composés avec les métaux 3d. Dans cette thèse, des comparaisons détaillées sont présentées entre les métaux, révélant des caractéristiques intrinsèques qui conduisent à des comportements différents en luminescence. D’autres exemples ont montré que la nature du métal avait un effet significatif autant sur l’énergie d’émission, particulièrement pour des complexes montrant des interactions intermoléculaires de type métal-métal. Cet aspect est aussi étudié, mais pour des centres métalliques impliqués dans des interactions intermoléculaires de type M…H-C, amenant des informations cruciales à la compréhension des différences. Dans la cadre de cette thèse, la variation structurale est explorée au-delà de la compression des liens métal-ligand en étudiant des complexes moléculaires au lieu de sels inorganiques. D’abord, l’effet des faibles variations structurales induites en température est présenté pour un complexe plan-carré de platine(II), montrant des variations spectroscopiques considérables. Ensuite, l’impact de la variation de l’angle L-M-L sur les spectres de luminescence est mesuré et discuté en comparant avec le modèle théorique « angular overlap model » (AOM), équivalent à la théorie du champ des ligands et particulièrement approprié pour les transitions d-d. Comme ces variations structurales sont habituellement négligées dans les études présentées en littérature, la caractérisation expérimentale de ces dernières amène un apport important au gain de connaissance dans le domaine. Les interactions intermoléculaires de type M…H-C sont de plus en plus étudiées en littérature, dont pour des complexes plan-carrés avec des métaux d8. Ces composés étant des luminophores, une caractérisation systématique de l’effet de ces interactions sur les propriétés de luminescence a pu être réalisée pour la première fois dans cette thèse. En utilisant la spectroscopie de luminescence à pression variable, des tendances quantitatives ont été extraites, renseignant sur la force de ce type d’interaction. D’autres facteurs déterminants sont aussi identifiés, dont l’alignement et la possibilité de mouvement des atomes qui interagissent, ainsi que l’effet de deutération. L’approche expérimentale avec la spectroscopie de luminescence à pression variable permet une caractérisation sensible non seulement des changements structuraux intramoléculaires, mais aussi intermoléculaires, détectant des variations subtiles même dans des interactions faibles de type M…H-C. Les résultats présentés sont plus directs et concluants que la même approche en spectroscopie vibrationnelle, s’avérant être une méthode prometteuse sur l’apport de données expérimentales pour ces interactions peu caractérisées., This thesis focuses on the luminescence of square-planar complexes of nickel(II), palladium(II), and platinum(II) in solid-state. A comprehensive and quantitative understanding of less-explored effects of the luminescence properties, such as variation of structure, metal, and intermolecular interactions, is obtained based on experimental spectra. The emission spectra are assigned as d-d electronic transitions from the first excited triplet to the ground state singlet for all complexes studied. Application of simple theoretical models allows one to study and compare their electronic structures. Luminescence spectra are measured and compared for many complexes with bidentate ligands and the same ligator atoms, mostly in the dithiocarbamate family. Pressure and temperature variations are applied to gain further quantitative information on these effects, contrasting with current studies reported in the literature measured at only one set of conditions. Structural data is obtained by X-ray crystallography and correlated with the luminescence spectra, showing important spectroscopic effects for even subtle structural variation. These effects have a defining influence on the energy and the shape of the luminescence spectra as conditions are varied, allowing a quantitative characterization and comparison among a family of complexes. The different molecular structures and intermolecular packings allow us to characterize the effects of the metal centers, of structural variations, and of M…H-C intermolecular interactions. Among examples in the literature, it is seen that the nature of the metal affects significantly the luminescence spectra, for instance in the intensity. However, detailed comparisons of a series with 3d, 4d, and 5d metals are rare, the intensity of emission of 3d metal complexes often being poor. In this thesis, detailed comparisons between similar complexes with 3d, 4d, and 5d metals are presented, revealing intrinsic characteristics responsible for differing luminescence properties. Other studies have shown that the metal affects greatly the emission energy, especially for complexes showing metal-metal intermolecular interactions. This aspect is also studied but for the metal involved in M…H-C interactions, bringing crucial information to the understanding of the differences. In this work, structural variations including and beyond metal-ligand bond compression are explored for molecular complexes at variable conditions instead of the more thoroughly studied inorganic salts. The effect of structural variations induced by temperature for the luminescence spectra is presented for a square-planar complex of platinum(II). The impact of the variation of the L-M-L angle as the structure changes with temperature or pressure is discussed, comparing the experimental results with those from the angular overlap model (AOM), equivalent to ligand-field theory and well adapted to the study of d-d transitions. Those characterizations supported by experimental evidence are new additions to structural variation considerations, as they are not usually taken into account in studies in the literature. M…H-C interactions are increasingly reported in the literature, and are present in some square-planar complexes with a d8 metal center. Being luminophores, the systematic comparison of the effect of these interactions on luminescence properties is performed for the first time in this thesis. By using luminescence spectroscopy at variable pressure, quantitative trends have been extracted to rationalize the relative strengths of such interactions. Other factors, such as alignment and possibility of movement of the interacting atoms, as well as the effect of deuteration, are revealed to be crucial to the characterization of the interaction. Luminescence spectroscopy at variable pressure as an experimental approach allows sensitive characterization of intramolecular and intermolecular structural changes, detecting even subtle variations in the weak M…H-C interactions. Results from this method are more direct and conclusive than those from vibrational spectroscopy at variable pressure. Thus, luminescence spectroscopy at variable pressure constitutes a promising method to gain experimental data on less-well characterized intermolecular interactions.