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Polycyclic aromatic hydrocarbons (PAH) are a prominent substance class with a variety of applications in molecular materials science. Their electronic properties crucially depend on the bond topology in ways that are often highly non-intuitive. Here, we study, using density functional theory, the triplet states of four PAHs based on the biphenylene motif finding dramatically different triplet excitation energies for closely related isomeric structures. These differences are rationalised using a qualitative description of Clar sextets and Baird quartets, quantified in terms of nucleus independent chemical shifts, and represented graphically through a recently developed method for visualising chemical shielding tensors (VIST). These results are further interpreted in terms of a 2D rigid rotor model of aromaticity and through an analysis of the natural transition orbitals involved in the triplet excited states showing good consistency between the different viewpoints. We believe that this work constitutes an important step in consolidating these varying viewpoints of electronically excited states.

Depending on the connectivity of solubilizing oligoethylene glycol (OEG) side chains to the π‐cores of amphiphilic naphthalene and perylene bisimide dyes, self‐assembly in water occurs either upon heating or cooling. Herein, we show that this effect originates from differences in the enwrapping capability of the π‐cores by the OEG chains. Rylene bisimides bearing phenyl substituents with three OEG chains attached directly to the hydrophobic π‐cores are strongly sequestered by the OEG chains. These molecules self‐assemble at elevated temperatures in an entropy‐driven process according to temperature‐ and concentration‐dependent UV/Vis spectroscopy and calorimetric dilution studies. In contrast, for rylene bisimides in which phenyl substituents with three OEG chains are attached via a methylene spacer, leading to much weaker sequestration, self‐assembly originates upon cooling in an enthalpy‐driven process. Our explanation for this controversial behavior is that the aggregation in the latter case is dictated by the release of “high energy water” from the hydrophobic π‐surfaces as well as dispersion interactions between the π‐scaffolds which drive the self‐assembly in an enthalpically driven process. In contrast, for the former case we suggest that in addition to the conventional explanation of a dehydration of hydrogen‐bonded water molecules from OEG units it is in particular the increase in conformational entropy of back‐folded OEG side chains upon aggregation that provides the pronounced gain in entropy that drives the aggregation process. Thus, our studies revealed that a subtle change in the attachment of solubilizing substituents can switch the thermodynamic signature for the self‐assembly of amphiphilic dyes in water from enthalpy‐ to entropy‐driven., Connectivity matters: A de novo design strategy is developed to generate supramolecular polymers upon heating (entropically driven) or cooling (enthalpically driven) based on the connectivity of amphiphilic wedges to the hydrophobic π‐core. Structural characterizations point towards the unique orientation of side chains in guiding this thermodynamic bias of self‐assembly in water (see figure).

Angle‐strained alkyne‐containing π‐conjugated macrocycles are attractive compounds both in functional materials chemistry and biochemistry. Their interesting reactivity as well as photophysical and supramolecular properties have been revealed in the past three decades. This review highlights the recent advances in angle‐strained alkyne‐containing π‐conjugated macrocycles, especially their synthetic methods, the bond angles of alkynes (∠sp at C≡C−C), and their functions. The theoretical and experimental research on cyclo[n]carbons and para‐cyclophynes consisting of ethynylenes and para‐phenylenes are mainly summarized. Related macrocycles bearing other linkers, such as ortho‐phenylenes, meta‐phenylenes, heteroaromatics, biphenyls, extended aromatics, are also overviewed. Bond angles of strained alkynes in π‐conjugated macrocycles, which are generable, detectable, and isolable, are summarized at the end of this review.

The synthesis of some novel donor-acceptor and acceptor-donor-acceptor systems containing a 2,2′-bi[3,2-b]thienothiophene donor block and various electron-accepting units is described alongside their photophysical properties studied using electrochemistry, optical spectroscopy and theoretical calculations. The obtained results show that the energy levels can be modulated by changing the strength of the acceptor unit. Among the three investigated end-groups, 1,1-dicyanomethylene-3-indanone exhibited the largest bathochromic shift and the lowest band gap suggesting the strongest electron-withdrawing character. Moreover, the emissive properties of the investigated systems vary greatly with the nature of the terminal group and are generally lower compared to their precursor aldehyde derivatives.

Modulating the structure of a photocatalyst at the molecular level can improve the photocatalytic efficiency and provides a guide for the synthesis of highly qualified photocatalysts. In this study, TiO2 was modified by various organic compounds to form different TiO2-based hybrid photocatalysts. 1,10-Phenanthroline (Phen) is an organic material with delocalized π-conjugated systems. It was used to modify TiO2 to form the hybrid photocatalyst Phen/TiO2. Furthermore, 1,10-phenanthrolin-5-amine (Phen-NH2) and 1,10-phenanthroline-5-nitro (Phen-NO2) were also used to modify TiO2 to form NH2-Phen/TiO2 and NO2-Phen/TiO2, respectively. The samples of TiO2, Phen/TiO2, NO2-Phen/TiO2, and NH2-Phen/TiO2 were carefully characterized, and their photocatalytic performance was compared. The results indicated that the photocatalytic efficiency followed the order of NH2-Phen/TiO2 > NO2-Phen/TiO2 > Phen/TiO2 > TiO2. It could be found that modifying TiO2 with different organic compounds containing delocalized π-conjugated systems could enhance the photocatalytic ability; furthermore, the level of this enhancement could be modulated by different delocalized π-conjugated systems.

Controlling the nanoscale morphology in assemblies of π-conjugated molecules is key to developing supramolecular functional materials. Here, we report an unsymmetrically substituted amphiphilic PtII complex 1 that shows unique self-assembly behavior in nonpolar media, providing two competing anti-cooperative and cooperative pathways with distinct molecular arrangement (long- vs. medium-slipped, respectively) and nanoscale morphology (discs vs. fibers, respectively). With a thermodynamic model, we unravel the competition between the anti-cooperative and cooperative pathways: buffering of monomers into small-sized, anti-cooperative species affects the formation of elongated assemblies, which might open up new strategies for pathway control in self-assembly. Our findings reveal that side-chain immiscibility is an efficient method to control anti-cooperative assemblies and pathway complexity in general.

The supramolecular polymerization of an acid‐sensitive pyridyl‐based ligand (L1) bearing a photoresponsive azobenzene moiety was elucidated by mechanistic studies. Addition of trifluoroacetic acid (TFA) led to the transformation of the antiparallel H‐bonded fibers of L1 in methylcyclohexane into superhelical braid‐like fibers stabilized by H‐bonding of parallel‐stacked monomer units. Interestingly, L1 dimers held together by unconventional pyridine–TFA N⋅⋅⋅H⋅⋅⋅O bridges represent the main structural elements of the assembly. UV‐light irradiation caused a strain‐driven disassembly and subsequent aggregate reconstruction, which ultimately led to short fibers. The results allowed to understand the mechanism of mutual influence of acid and light stimuli on supramolecular polymerization processes, thus opening up new possibilities to design advanced stimuli‐triggered supramolecular systems., A look into the self‐assembly: Detailed mechanistic insights into the supramolecular polymerization of an acid‐sensitive photoresponsive pyridyl‐based ligand are reported. Addition of acid (TFA) caused the transformation of long twisted fibers into superhelical braid‐like assemblies stabilized by aromatic, H‐bonding, and van der Waals interactions through a dimerization event involving two unconventional pyridine–TFA N⋅⋅⋅H⋅⋅⋅O bridges. Photoirradiation led to a strain‐driven disassembly of the superhelical fibers and subsequent attenuated growth into short fibers after reconstruction.

Cooperative π–π interactions and H‐bonding are frequently exploited in supramolecular polymerization; however, close scrutiny of their mutual interplay has been largely unexplored. Herein, we compare the self‐assembly behavior of a series of C 2‐ and C 3‐symmetrical oligophenyleneethynylenes differing in their amide topology (N‐ or C‐centered). This subtle structural modification brings about drastic changes in their photophysical and supramolecular properties, highlighting the reciprocal impact of H‐bonding vs. preorganization on the evolution and final outcome of supramolecular systems., To match or not to match: Detailed self‐assembly studies of a series of C2‐ and C3‐symmetrical π‐systems that differ in the amide connectivity (N‐ vs. C‐centered) were used to examine the reciprocal impact of H‐bonding and preorganization on the evolution of self‐assembled structures.

Aromaticity is a central concept in chemistry, pervading areas from biochemistry to materials science. Recently, chemists also started to exploit intricate phenomena such as the interplay of local and global (anti)aromaticity or aromaticity in non‐planar systems and three dimensions. These phenomena pose new challenges in terms of our fundamental understanding and the practical visualisation of aromaticity. To overcome these challenges, a method for the visualisation of chemical shielding tensors (VIST) is developed here that allows for a 3D visualisation with quantitative information about the local variations and anisotropy of the chemical shielding. After exemplifying the method in different planar hydrocarbons, we study two non‐planar macrocycles to show the unique benefits of the VIST method for molecules with competing π‐conjugated systems and conclude with a norcorrole dimer showing clear evidence of through‐space aromaticity. We believe that the VIST method will be a highly valuable addition to the computational toolbox., A method for the visualisation of chemical shielding tensors (VIST) is developed, which provides a graphical representation of aromaticity and antiaromaticity, their local variations, and anisotropy. The method provides unique insight into fascinating phenomena such as the interplay of aromaticity and antiaromaticity in macrocycles with competing π‐conjugated systems.

Controlling the supramolecular self-assembly of π-conjugated systems into defined morphologies is a prerequisite for the preparation of functional materials. However, the role of solvents of opposed polarity in the self-assembly of a given building block still remains an open question. Herein, we unravel the effect of aggregation-inducing solvent systems of opposed polarity (aqueous vs. non-polar media) on the supramolecular assembly of a new bolaamphiphilic Pt(II) complex. Morphological analysis of the respective aggregates reveals a restricted aggregate growth in aqueous media into spherical nanoparticles and a non-restricted 2D-nanosheet formation in non-polar media, while the molecular packing remains preserved. These findings are attributed to a considerably more efficient solvation and, in turn, increased steric demand of the hydrophilic chains in aqueous media than in nonpolar media. Kontrolle über supramolekulare Sebstassemblierung von π-konjugierten Systemen in definierte Morphologien ist eine Grundvoraussetzung für die Herstellung funktioneller Materialen. Allerdings ist der Einfluss von Lösungsmitteln gegensätzlicher Polarität auf die Selbstassemblierung ein und desselben Grundbausteins noch immer eine offene Frage. In dieser Arbeit zeigen wir den Einfluss zweier aggregationsinduzierender Lösungsmittel gegensätzlicher Polarität (wässrig gegen unpolar) auf die supramolekulare Assemblierung eines neuartigen bolaamphiphilen Pt(II) Komplex. Die Analyse der Morphologien der jeweiligen Aggregate zeigt ein restriktives Wachstum in wässrigen Medien in sphärische Nanopartikel auf, während ein ungehindertes Wachstum zu zweidimensionalen Platten in unpolaren Lösungsmitteln beobachtet wird, obwohl die molekulare Packung erhalten bleibt. Diese Beobachtungen werden der effektiven Solvatisierung und in der Folge dem erhöhten sterischen Anspruch der hydrophilen Seitenketten in wässrigen Medien zugesprochen.

In order to understand the electronic contribution of the thienopyrazine building block on the electronic properties of π-conjugated systems, small molecules containing thiophene and thienopyrazine moieties are synthesized and jointly studied by theoretical (DFT) and experimental methods (UV-Vis, UPS). Taking advantages of these preliminar attractive results, four low band gap extended structures have been elaborated on the base of Donor-Acceptor-Donor sequences (DAD); these elongated π-conjugated molecules exhibit noticeable electronic and absorption properties spreading from the near UV to NIR regions.

Besides their widespread use in coordination chemistry, 2,2’‐bipyridines are known for their ability to undergo cis–trans conformational changes in response to metal ions and acids, which has been primarily investigated at the molecular level. However, the exploitation of such conformational switching in self‐assembly has remained unexplored. In this work, the use of 2,2’‐bipyridines as acid‐responsive conformational switches to tune supramolecular polymerization processes has been demonstrated. To achieve this goal, we have designed a bipyridine‐based linear bolaamphiphile, 1, that forms ordered supramolecular polymers in aqueous media through cooperative aromatic and hydrophobic interactions. Interestingly, addition of acid (TFA) induces the monoprotonation of the 2,2’‐bipyridine moiety, leading to a switch in the molecular conformation from a linear (trans) to a V‐shaped (cis) state. This increase in molecular distortion along with electrostatic repulsions of the positively charged bipyridine‐H+ units attenuate the aggregation tendency and induce a transformation from long fibers to shorter thinner fibers. Our findings may contribute to opening up new directions in molecular switches and stimuli‐responsive supramolecular materials., Switch and tune! The trans–cis conformational switching of 2,2’‐bipyridine in response to acid was exploited to tune supramolecular polymerization processes. For this purpose, the aqueous self‐assembly of a bipyridine‐based linear bolaamphiphile that self‐assembles under standard conditions into cooperative supramolecular polymers was investigated. Interestingly, acid‐triggered protonation of the bipyridine unit induces a molecular conformational change from linear (trans) to cis (V‐shaped) that leads to an attenuated supramolecular growth into shorter fibers.

The continuous efforts devoted to improving the performances in organic photovoltaics (OPV) have enhanced the photoconversion efficiencies over 18% so far. However, a critical vision of the state-of-the-art publications highlights that thehighest efficiencies are generally paired with an enhancement of the synthetic complexity of both the materials (donor and acceptor) and the fabrication procedure. That is the reason why the preparation of simpler and less expensive materials is that crucial. In this regard, after a first chapter reviewing the recent progress in OPV, a second chapter is focused on the synthesis of D-π-A molecules based on the N-methyl-N-phenylthiophen-2-amine (MPTA) electron-donor unit, which was not previously used in the field. A series of derivatives is synthesized by modulating the π-spacer and the electron-withdrawing group A and theimpact on their optical, electrochemical and photovoltaic properties is naturally investigated. A third chapter is related to the structural modification of a recently reported push-pull molecule, namely TPA-T-DCV-Ph. Its additional phenyl ring in the accepting moiety led to a higher exciton diffusion length and therefore photoconversion efficiency in comparison to the well-known TPA-T-DCV. Hence, two different structural modifications of this donor are reported. Eventually, a fourth chapter is related to the functionalization of a promising and unexplored rylene, namely the benzothioxanthene (BTXI) whose most attractive features are its low synthetic cost and outstanding optical and electrochemical properties. Thus, its reactivity is explored in a deeper level and the properties of the new derivatives are studied., Les efforts continus développés dans le domaine du photovoltaïque organique (OPV) ont permis d’améliorer les rendements de photo conversion jusqu’à 18%. Cependant, une vision critique des publications met en évidence que les rendements les plus élevés sont généralement associés à une augmentation de la complexité synthétique des matériaux (donneur et accepteur) et de la procédure de fabrication. C'est la raison pour laquelle la préparation de matériaux plus simples et moins chers est si cruciale. Après un premier chapitre examinant les progrès récents en OPV, un deuxième chapitre traite de la synthèse des molécules D-π-A dérivées du Nméthyl-N-phénylthiophène-2-amine (MPTA), un groupe donneur d’électron D encore non utilisé auparavant en OPV. Une série de dérivés a été synthétisée en modulant l'espaceur π-conjugué et le groupe attracteur d'électrons A, et l'impact sur leurs propriétés optiques, électrochimiques et photovoltaïques a naturellement été étudié. Un troisième chapitre porte sur différentes approches de modification structurale d'une molécule push-pull récemment décrite dans la littérature, à savoir le TPAT-DCV-Ph. La présence du groupe phényle (Ph) terminal a conduit à une longueur de diffusion d'exciton plus élevée et ainsi à un meilleur rendement de photo conversion par rapport à la molécule pushpull de référence TPA-T-DCV. Finalement, un quatrième chapitre se focalise sur la fonctionnalisation d'un bloc prometteur et très peu exploré, le benzothioxanthène (BTXI). Ainsi, sa réactivité a été étudiée et les propriétés des nouveaux dérivés sont discutées.

We exploited the inherent geometrical isomerism of a PtII complex as a new tool to control supramolecular assembly processes. UV irradiation and careful selection of solvent, temperature, and concentration leads to tunable coordination isomerism, which in turn allows fully reversible switching between two distinct aggregate species (1D fibers↔2D lamellae) with different photoresponsive behavior. Our findings not only broaden the scope of coordination isomerism, but also open up exciting possibilities for the development of novel stimuli‐responsive nanomaterials., Size matters: Coordination isomerism was exploited for the first time to control the morphology of a supramolecular polymer. These observations pave the way for novel stimuli‐responsive materials and offer a new approach for size control in self‐assembled systems.

Supramolecular gels containing porphyrins and phthalocyanines motifs are attracting increased interests in a wide range of research areas. Based on the supramolecular gels systems, porphyrin or phthalocyanines can form assemblies with plentiful nanostructures, dynamic, and stimuli-responsive properties. And these π-conjugated molecular building blocks also afford supramolecular gels with many new features, depending on their photochemical and electrochemical characteristics. As one of the most characteristic models, the supramolecular chirality of these soft matters was investigated. Notably, the application of supramolecular gels containing porphyrins and phthalocyanines has been developed in the field of catalysis, molecular sensing, biological imaging, drug delivery and photodynamic therapy. And some photoelectric devices were also fabricated depending on the gelation of porphyrins or phthalocyanines. This paper presents an overview of the progress achieved in this issue along with some perspectives for further advances.

A series of molecules in which 9H-carbazole (electron donor, D) and 2,2':6',2''-terpyridine (electron acceptor, A) are connected through rigid π-conjugated bridges (D-π-A systems) have been synthesized and their photophysical properties examined in detail, with the support of DFT calculations. The bridges are made of different sequences of ethynylene, phenylene, and anthracene groups. The synthetic strategies involve condensation of 2-acetylpyridine with the aromatic aldehyde moiety on different functionalized π-conjugated bridges and couplings with carbazole derivatives. The system incorporating anthracene in the bridge shows the typical absorption and emission fingerprints of this polycyclic hydrocarbon. The other systems have HOMOs and LUMOs centred, respectively, over the carbazole and the bridge and exhibit solvatochromic charge-transfer (CT) luminescence with high photoluminescence yield up to 70 %, except when an ethynylene unit is directly attached to the carbazole ring, due to a trans-bent non-emissive π-σ* excited state.

Intense development of organicphotovoltaics (OPVs) in the last twenty years led toincreasing photoconversion efficiencies, which are nowabout 14 %. Electron donating (D) and electronaccepting (A) materials used in such solar cells havereceived considerable attention from the academicsaround the world and are still continuously improved.However, those performing materials requirenumerous synthetic steps and the use of toxicchemicals to be produced, which jeopardize their futurecommercialization.In this context, after a first chapter reviewing recentprogresses in OPV, a second chapter will focus on asimple dye, namely the diketopyrrolopyrrole (DPP) andits use in p and n type materials.New molecular DPP-based acceptors weresynthetized and the impact of the solubilizing chainsalong with the -conjugated spacer on theirphotovoltaic properties are discussed. Then, a newDPP and spirobifluorene (SBF) based copolymer wassynthetized by a more environmentally friendlysynthetic route and its photovoltaic properties aredetailed.A third chapter focuses on the benzothioxantheneimide (BTXI), a building block that has not yettriggered much interest in the organic electronicscommunity. Electronic properties of the latter werecharacterized and, after its synthetic pathway wasoptimized, new BTXI based molecular materials weresynthesized and used in organic solar cells andorganic thin-film transistors (OTFTs)., Le développement du photovoltaïque organique (OPV) depuis une vingtaine d’années a permis une hausse significative des rendements de photoconversion qui atteignent aujourd’hui 14 %. Ces progrès résultent à la fois de l’optimisation de l’architecture des cellules solaires organiques (OSCs) ainsi que de la mise au point de matériaux donneurs (D) et accepteurs (A) d’électrons performants. Cependant, la complexification notable des voies de synthèse de ces matériaux limite la production à grande échelle de modules OPV en raison de coûts de production élevés et de génération de nombreux déchets. Dans ce contexte et après un premier chapitre retraçant l’historique de l’OPV et les découvertes ayant contribuées à son succès, un deuxième chapitre traite de l’utilisation d’un colorant simple, le dicétopyrrolopyrrole (DPP), dans des matériaux de type p ou n. De nouveaux accepteurs moléculaires ont été synthétisés et l’impact de la nature des chaines solubilisantes et de l’espaceur π-conjugué sur leurs propriétés optoélectroniques est présenté. Un nouveau copolymère de DPP et de spirobifluorène, facilement accessible par des voies de synthèse plus respectueuses de l’environnement, a aussi été développé et caractérisé lors de ce travail et ses performances photovoltaïques sont détaillées. Un troisième chapitre se focalise sur le benzothioxanthène imide (BTXI), bloc encore méconnu dans le domaine de l’électronique organique. Les propriétés électroniques de ce dernier ont été caractérisées et, après une optimisation de sa voie de synthèse, des dérivés de BTXI ont été intégrés avec succès dans des dispositifs de type OSCs et transistors organiques en couche mince (OTFTs).

Statistical copolymerization plays a key role in many biological and technological processes; however, mechanistic understanding of the formation of analogous supramolecular counterparts remains limited. Herein, we report detailed insights into the supramolecular co‐assembly of two π‐conjugated PdII and PtII complexes, which in isolation self‐assemble into flexible fibers and nanodisks, respectively. An efficient single‐step co‐assembly into only one type of nanostructure (fibers or nanodisks) takes place if any of the components is in excess. In contrast, equimolar mixtures lead to PdII‐rich fiber‐like co‐assemblies by a statistical co‐nucleation event along with a residual amount of self‐sorted nanodisks in a stepwise manner., Go nano! Mechanistic insights into the supramolecular co‐assembly of two structurally related π‐conjugated PdII and PtII complexes are reported. While the final nanostructure morphology upon co‐assembly (fibers or nanodisks; see figure) is dictated by the component that is present in excess, equimolar mixtures lead to PdII‐rich co‐assembled fibers by a co‐nucleation event along with a residual amount of self‐sorted nanodisks in a stepwise manner.

This manuscript describes the synthesis and characterization of new molecular systems based on phosphorus atom: we developed and studied π-conjugated systems based on phosphole and secondly supramolecular assemblies with phosphine ligand have been studied. Firstly, an introduction to the phosphole chemistry (history, synthesis methods, integration into π-conjugated systems) is presented. The first chapter describes the synthesis and physico-chemical study of phospholes derivatives having an extended π-system for the development of orange-red emitters in organic light-emitting diodes (OLEDs). Different molecular engineering involving the triple bond leads to modifications of the optical properties of the synthesized compounds by red-shifting their absorption and/or emission maxima. Chapter II describes the synthesis and the physical properties of complexes using phosphole based π-systems as linkers between two metal centers. New Fe (II), Pt (II) and Au (I) complexes have been developed and the electronic communication between the two metals is studied. The second part of the thesis work starts with a review on the emissive Cu(I) complexes. In Chapter III, are presented the syntheses, the structural and optical studies of new solid-state emissive supramolecular assemblies synthesized from pre-assembled Cu(I) molecular clips and stabilized by phosphine ligands (dppm or dpmp) with cyano ligands as linkers. Then in the final chapter new Cu(I) complexes are synthesized by using organic ligands with terminal nitrile functions as linkers. The solid-state luminescence properties of these new Cu(I) derivatives are studied according to their external environment and thermochromism, vapochromism and mechanochromism phenomena have been demonstrated for some of them., Ce manuscrit décrit la synthèse et la caractérisation de nouveaux systèmes moléculaires à base de phosphore : dans la première partie sont étudiés des dérivés π-conjugués du cycle phosphole et la seconde partie fait état d'assemblages supramoléculaires à ligands phosphines. Tout d'abord, une introduction à la chimie du phosphole (historique, méthodes de synthèse, insertion dans des systèmes π-conjugués) est présentée. Le premier chapitre décrit la synthèse et l'étude physico-chimique de dérivés phospholes possédant un système π étendu afin de les utiliser en tant qu'émetteurs oranges-rouges dans des diodes électroluminescentes organiques (OLEDs). Différentes modifications chimiques de la triple liaison sont ensuite mises en place pour modifier les propriétés optiques des dérivés synthétisés en déplaçant leurs maximas d'absorption et/ou d'émission vers les plus grandes longueurs d'onde. Le chapitre II décrit la synthèse et l'étude de complexes utilisant une brique phosphole acétylénique comme connecteur conjugué entre deux centres métalliques. De nouveaux complexes de Fe(II), Pt(II) et d'Au(I) ont ainsi été développés et la communication électronique entre les métaux est étudiée. La deuxième partie de ces travaux de thèse commence avec un historique sur les complexes de Cu(I) luminescents, qu'ils soient mono- ou polynucléaires, qu'ils possèdent une structure de forme cubane ou autres. Dans le chapitre III, sont présentées les synthèses, les études structurales et optiques de nouveaux assemblages supramoléculaires émissifs à l'état solide synthétisés à partir de clips moléculaires de Cu(I) préassemblés et stabilisés par des ligands phosphines (dppm ou dpmp) avec des ligands connecteurs de type cyano CN-. Ensuite, le dernier chapitre utilise cette même stratégie de synthèse en utilisant des ligands connecteurs organiques à fonctions nitriles terminales et de nouveaux complexes de Cu(I) discrets ou étendus sont caractérisés. Tout au long de cette deuxième partie, les propriétés de luminescence des dérivés de Cu(I) sont étudiées en fonction de leur environnement extérieur et des phénomènes de thermochromisme, de vapochromisme et de mécanochromisme sont mis en évidence chez certains d'entre eux.

International audience; A synthetic route to novel benzofuran fused silole derivatives is described and the new compounds were fully characterized. These compounds showed optical and electrochemical properties that differ from their benzothiophene analog. Preliminary results show that these derivatives can be used as blue emitters in organic light emitting devices (OLEDs) illustrating the potential of these new compounds for opto-electronic applications.

Different D–π–A push–pull molecules in which dipicolylamine (DPA) is used as the donor group, different diazines as the acceptor groups, and styryl as the π-conjugated spacer have been synthesized in a straightforward manner by aldol condensation of 4-(di-2-picolylamino)benzaldehyde and the appropriate methyldiazine. All of the compounds showed π–π* transitions in the UV or visible region and the emission of yellow-green light upon irradiation. Significant red shifts were observed in the fluorescence emission maxima of these compounds on increasing the solvent polarity, a finding that suggests the formation of an intramolecular charge-separated emitting state that is also supported by semi-empirical calculations. In some cases, protonation led to marked color changes, thus showing the ability of these molecules to function as colorimetric pH sensors. The DPA and diazine units can act as coordination sites for metal cations such as Zn 2+ , Cd 2+ or Hg 2+ , leading to a blue or red shift in the fluorescence spectra due to the change in the intramolecular charge transfer properties. This phenomenon could become a powerful tool for the creation of multiple emission colors with a single molecule after suitable design.

Klik reakcija, danas vrlo popularna reakcija korištena u brojnim organskim sintezama, predstavljena je u ovom radu kao jednostavna i eknomična metoda dobivanja novih derivata benztiazola, D-π-A kromofora s potencijalnom primjenom u kemijskim senzorima. Opisani su mnogi derivati benztiazola koji se koriste u senzorici i optoelektronici te su objašnjene njihove optičke karakteristike. Na temelju poželjnih optičkih svojstava koja zahtijevaju specifičnu strukturu molekule (senzora), predložena je sinteza 3 serije heterocikličkih kromofora s benztiazolnom jezgrom temeljena na klik reakciji te je navedena mogućnost njihove primjene u optičkim senzorima za detekciju teških metala u vodi (primjerice žive). Click reaction is widely used in many organic synthesis as an easy and economic method for the preparation of novel D-π-A chromophores applicable in optical chemical sensors. In this work, click synthesis of novel benzthiazole derivatives is presented. Many benzothiazole derivatives used in sensorics and optoelectronics have been described, as well as their optical characteristics. Based on desireable optical properties that are achieved by adjusting the structure of the sensing molecule, the synthesis of three series of heterocyclic chromophores with benzthiazole core that are based on „click“ reaction is proposed. The possibilites of using these chromophores in optical sensors for detection of heavy metals, like mercury (II), in water, is discussed.

Two new quadrupolar 4H-pyran-4-ylidene fluorophores (3) derived from indole were prepared in good yields through condensation of 5-methyl-1H-indole-3-carbaldehyde with the acceptor precursors 2-(2,6-dimethyl-4H-pyran-4-ylidene)malononitrile (1) and 1,3-diethyl-dihydro-5-(2,6-dimethyl-4H-pyran-4-ylidene)-2-thiobarbituric (2), in the presence of a catalytic amount of piperidine. These building blocks were prepared by Knoevenagel condensation of the corresponding ketone precursor with malononitrile or 1,3-diethyl-dihydro-2-thiobarbituric acid. The new compounds were completely characterized by the usual spectroscopic techniques (UV-vis., FT-IR and multinuclear NMR - 1H, 13C)., Portuguese NMR network (PTNMR, Bruker Avance III 400-Univ. Minho). Thanks are due to Fundação para a Ciência e Tecnologia (Portugal) for financial support to the Portuguese NMR network (PTNMR, Bruker Avance III 400-Univ. Minho), FCT and FEDER (European Fund for Regional Development)-COMPETEQREN-EU for financial support to the research centre CQ/UM [PEst-C/QUI/UI0686/2013 (FCOMP-01- 0124-FEDER-037302)] and a post-doctoral grant to R.M.F. Batista (SFRH/BPD/79333/2011)., info:eu-repo/semantics/publishedVersion

As part of an on-going research to develop efficient heterocyclic systems for optical applications (NLO, photochromic, chemosensor, etc) we report in this work the synthesis and the photophysical characterization of novel heterocyclic imines 1a-b and 2, functionalized with thiadiazole or benzothiazole as acceptor groups linked to an aryl ring., Fundação para a Ciência e a Tecnologia (FCT)

This thesis describes the synthesis and the characterization of new molecules including an organophosphorous unit, the phosphole ring. Some molecules have been used to build devices like organic light emitting diodes or organic photovoltaic cells.The first chapter describes the state of the art of the phosphole chemistry in organic materials between 2010 and 2013. The second chapter describes molecules having a tuneable twist angle allowing a fine control of the properties of the molecules like the HOMO-LUMO gap. One of those molecules has been used to build a white organic light emitting diode. The third chapter of this thesis presents an interesting three dimensional structure, the 1,1'-biphosphole. Beside this three dimensional structure, the molecules possess an original conjugation mode, the σ-π conjugation which allows a decrease of the HOMO-LUMO gap. One molecule from this chapter was used as absorber in organic photovoltaic cell. In the second part of this chapter, the 1,1'-biphosphole structure shows an interesting reactivity toward nucleophilic attack in order to functionalize the phosphorus center. This reactivity has been used to make new molecules and offer the opportunity to attach a wide range of substituents to the phosphorus atom in order to tune the properties of the molecules. The fourth chapter deals with the coordination chemistry of the phosphole in order to realize new ortho-metalated complexes. New Ir(III) and Rh(III) complexes have been synthesized and characterized., Ce manuscrit décrit la synthèse et la caractérisation de nouvelles molécules incluant un cœur organophosphoré, le phosphole. Certaines de ces molécules ont été utilisées pour la fabrication de dispositifs OLEDs ou de cellules photovoltaïques organiques. Le premier chapitre fait un état de l'art de la chimie du phosphole dans le domaine des matériaux organiques entre 2010 et 2013. Le second chapitre décrit la synthèse et l'étude physico-chimique de molécules qui permettent de moduler l'angle de torsion dans les systèmes π conjugués pour faire varier les propriétés optiques et rédox. Une de ces molécules a permis la fabrication d'une diode blanche organique. Le troisième chapitre de ce manuscrit présente une structure tridimensionnelle intéressante, le 1,1-biphosphole. En plus de posséder une structure tridimensionnelle, ces structures présentent un mode de conjugaison original, la conjugaison σ-π, qui permet de réduire l'écart HO-BV de nos systèmes. Une de ces molécules a permis la fabrication de la première cellule photovoltaïque organique avec un dérivé du phosphole inséré dans la couche active. Dans une deuxième partie, ce chapitre traite également de la réactivité originale du 1,1'-biphosphole qui permet de fonctionnaliser l'atome de phosphore par une simple substitution nucléophile, permettant d'insérer une grande variété de substituants pour moduler les propriétés des molécules. Pour finir, ce manuscrit présente un quatrième chapitre qui implique le phosphole comme unité coordinante afin de réaliser des nouveaux complexes qui permettent de réaliser une ortho-métallation par activation C-H. De nouveaux complexes ortho-métallés d'Ir(III) et de Rh(III) ont été synthétisés et caractérisés.

International audience; Terthienyls functionalized at their two outer β,β′-positions by 2- and 3-(thienyl)cyanovinyl groups have been synthesized by basic condensation. The analysis of their electronic properties by UV–vis spectroscopy and cyclic voltammetry shows that the mode of derivatization affects essentially the LUMO level of the conjugated system.

A series of formyl-substituted 5-aryl-2,2´-bithiophenes 5 were synthesized using two different methods: Vilsmeier-Haack-Arnold reaction (VHA) or through Suzuki coupling. The synthesis of compounds 5 through the Vilsmeier-Haack-Arnold reaction, starting from inexpensive and easily available precursors such as acetophenones, gave the title compounds in low yields after four reaction steps. On the other hand Suzuki coupling of functionalized aryl boronic acids 7 and the 5-bromo-5´-formyl-2,2´-bithiophene 6 gave compounds 5 in good yields in only one step., Fundação para a Ciência e a Tecnologia (FCT)

A series of new heterocyclic chromophores 3-6 were synthesised in moderate to excellent yields by condensation of 5,6-phenantroline-dione with formyl-thiophene derivatives 1-2 in the presence of ammonium acetate in glacial acetic acid. These chromophores possess a (oligo)thienyl- π-conjugated system attached to an imidazophenanthroline moiety. These derivatives were evaluated concerning their solvatochromic properties, thermal stabilities and molecular optical nonlinearities., Fundação para a Ciência e Tecnologia (FCT) - projecto PTDC/QUI/66250/2006, bolsa de doutoramento a R.M.F. Batista SFRH/BD/36396/2007), (FCT-UNL) REQUIMTE.

This work deals with the synthesis and the characterization of new p-conjugated systems derived from oligothiophenes that form monolayers on gold with the perspective of applications in molecular electronic.The first bibliographic part summarizes the principle of self-assembled monolayers (SAMs) and presents some of their various applications.The second and third chapters describe the synthesis of 2,2'-bithiophene derivatives for the elaboration of SAMs on gold. The decrease of oxidation potential and increase of reactivity due to the insertion of 3,4-ethylenedioxythiophene in a bithiophene structure associated with the well-organized monolayer make possible the efficient electropolymerization of the corresponding SAM. A synthetic methodology was developed to prepare 2,2-bithiophene derivatives substituted by two differently protected thiolate groups. These compounds have been used to form gold monolayers that can be further modified chemically or electrochemically.The two last chapters concern essentially the synthesis of mono- and dithiol quaterthiophenes, their characterization and their immobilization on gold. The dithiol derivatives lead to the formation of polydisulfide after electrochemical oxidation in solution and their double fixation on gold allows us to prepare more stable monolayers. Dithiol quaterthiophenes functionalized with various groups such as polyether chains or ferrocene have been synthesized, characterized in solution and then immobilized as gold monolayers. Depending on their functionalization, these surfaces show complexation properties toward Pb2+ ions or present the advantage to be further functionalized., Ce travail porte sur la synthèse et la caractérisation de nouveaux systèmes conjugués linéaires de la famille des oligothiophènes, aptes à former des monocouches sur l'or avec des perspectives d'applications en électronique moléculaire.Le premier chapitre bibliographique est consacré à une description des monocouches auto-assemblées (SAMs) et à quelques exemples d'application.Les deuxième et troisième chapitres sont relatifs à la synthèse de dérivés du 2,2'-bithiophène pour l'élaboration de SAMs sur l'or. Un dérivé bithiophène constitué d'un motif 3,4-éthylènedioxythiophène a conduit à la formation de SAMs parfaitement organisées. Ce résultat ainsi que la diminution du potentiel d'oxydation et l'augmentation de la réactivité du dérivé bithiophène associées à la présence du motif 3,4-éthylènedioxythiophène permettent d'électropolymériser les SAMs correspondantes de façon efficace. Une méthodologie de synthèse a ensuite été développée pour la préparation de dérivés du 2,2'-bithiophène substitués par deux groupes thiolate différemment protégés. Ces composés ont été utilisés pour préparer des monocouches dont la structure a pu être modifiée a posteriori par voie chimique ou électrochimique.Les deux derniers chapitres de ce travail portent essentiellement sur la synthèse de quaterthiophènes mono- et dithiol, leur caractérisation et leur immobilisation sur l'or. Les dérivés dithiol conduisent après oxydation électrochimique en solution à la formation de polydisulfure et leur double accroche sur l'or permet d'obtenir des monocouches très stables. Enfin, des quaterthiophènes dithiol substitués par divers groupes fonctionnels (chaînes polyéther ou ferrocène) ont été synthétisés, caractérisés en solution puis immobilisés sous forme de monocouches sur l'or. Selon les cas, ces dernières présentent des propriétés de complexation des ions Pb2+ ou offrent la possibilité d'être fonctionnalisées.