Dissertations / Theses on the topic 'Supramolecular organic chemistry'
To see the other types of publications on this topic, follow the link: Supramolecular organic chemistry.
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 dissertations / theses for your research on the topic 'Supramolecular organic chemistry.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
1
Skabara, Peter John. "Functionalised tetrathiafulvalenes in supramolecular chemistry." Thesis, Durham University, 1994. http://etheses.dur.ac.uk/10491/.
Full textAbstract:
Using a range of functionalised tetrathiafulvalene (TTF) derivatives, developed at Durham, the first examples of covalently linked TTF-ferrocene systems have been prepared. The redox properties of these molecules, as studied by cyclic voltammetry, provide evidence that these species are efficient π-electron donors. Highly reactive 1,3-dithiole Wittig and Wittig-Homer reagents have been used in the synthesis of complex mixed redox-active systems containing ferrocenyl units. A series of [3]- and [4]-dendralenes has also been developed from this synthetic methodology. Cyclic voltammetry shows that tri- and tetracationic states can be achieved with these systems at relatively low potentials. The potential for vinyl-TTF compounds to undergo [4+2] cycloaddition has been investigated for the first time. The peripheral C=C unit of TTF, together with the adjacent vinylic substituent, is able to act as the diene functionality in Diels-Alder reactions. Remarkably, the π-delocalisation within the TTF moieties is readily disrupted by the addition of strong dienophiles. The reactivity of lithiated TTF towards aldehydes and ketones has established an array of hydroxy-functionalised TTF, bis-TTF and TTF-ferrocene derivatives. The conducting and magnetic properties of the chloranil charge transfer salt of one of these species is also reported.
2
Rather, Elisabeth. "Supramolecular metal-organic and organic materials." [Tampa, Fla.] : University of South Florida, 2004. http://purl.fcla.edu/fcla/etd/SFE0000267.
Full text
3
Roshandel, Sahar. "Supramolecular devices as selective receptors." Thesis, California State University, Long Beach, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=1597789.
Full textAbstract:
We have found that calixarenes are good receptors of choline (trimethylammonium group) and they have strong affinity to form host-guest complexes with a variety of molecules carrying this moiety. Furthermore, the ability of lower rim carboxylic acid calix[n]arenes and upper rim phosphonic acid functionalized calix[4]arene to transport choline-conjugated drugs through a liquid membrane was discovered. The results demonstrate that these systems are highly efficient toward transporting choline-conjugated targets, as well as neurotransmitters that possess ionizable amine termini. The breadth of compounds that are transported is significant, facing limitations only when the payloads become extremely lipophilic. These developments reveal new approaches towards attempting synthetic receptor mediated selective small molecule transport in vesicular and cellular systems.
4
Sisson, Thomas Michael 1966. "Crosslinking polymerization in supramolecular assemblies." Diss., The University of Arizona, 1997. http://hdl.handle.net/10150/282566.
Full textAbstract:
Supramolecular assemblies are composed of noncovalently associated molecules which organize in water to yield 2-D and 3-D architectures. Crosslinking polymerization of supramolecular assemblies provides an effective means to modify their chemical and physical properties. Two methods of characterizing crosslinked polymeric assemblies were developed. These techniques rely on experimentally observed changes in polymer solubility and assembly stability in the presence of nonionic surfactants. The results show an inefficient crosslinking mechanism in organized media compared to isotropic polymerization. Two models rationalizing the inefficient crosslinking observed in organized media were proposed. Symmetrical crosslinking agents were synthesized to test the models. These results suggest intramolecular memorialization is an important process in the efficiency of crosslinking. The polymerization of a heterobifunctional lipid with two polymerizable groups in the same acyl chain separated by a six carbon spacer yielded a novel linear ladder-like polymer architecture. The two reactive groups are in regions of different polarity allowing for the simultaneous, selective, and sequential polymerization depending on the initiation chemistry employed. A second heterobifunctional lipid was designed and synthesized with a longer spacer between the two reactive groups. Polymerization of vesicles gave stable polymeric vesicles. The results from the crosslinking and redox polymerization studies on 2-D assemblies were applied to the inverted hexagonal and bicontinuous cubic phases. Phase behavior is characterized before and after crosslinking polymerization principally by variable temperature ³¹NMR. γ-Initiated polymerization of bis-lipids was studied to evaluate their sensitivity to ionizing radiation. The reactive moiety effects the initial rate of polymerization, extent of polymerization, and inhibition by oxygen. A preliminary investigation of polymerizable ion-paired amphiphiles (IPA) showed polymerization methods commonly used for zwitterionic lipids can be applied to IPA. This is the first report of polymerization of reactive groups in the anionic acyl chain of an ion-paired amphiphile.
5
Childs, Laura Jennifer. "Supramolecular assemblies based on imine and azo chemistry." Thesis, University of Warwick, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.269076.
Full text
6
Young, Michael Christopher. "Self-Assembly of Functionalized Supramolecular Structures." Thesis, University of California, Riverside, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3644049.
Full textAbstract:
Enzymes are capable of exquisite selectivity in catalysis chemical reactions because of a well-evolved mechanism that binds substrates in internal active sites based on size and shape complementarity. The cavities of these enzymes are decorated with organic or inorganic groups which can promote reactivity once the substrate is non-covalently bound. Synthetic molecular hosts to date have been able to bind to substrates in a similar, biomimetic fashion, but functionalized molecular hosts are still virtually unknown.
One convenient way to prepare molecular hosts is by the self-assembly of organic coordinating ligands with suitable metal salts. The reversible dative bonds holding these cage structures together allow incorrect products to break apart and reform, favoring creation of the most thermodynamically stable product. This leads to discrete, solution phase cages that can function as cavity-containing hosts. Some of these hosts have shown efficacy as catalysts for pericyclic reactions due to favorable transition states of the bound substrates. These cages, however, fail to orient reactive functional groups into their interiors. Truly biomimetic cages will require modifying traditional self-assembled targets to incorporate these reactive functionalities.
This work explores the self-assembly of metal-organic cages displaying covalent modifications on their interior. Incorporation of unreactive and poorly reactive groups was found to have a significant impact on the outcome of the self-assembly process. Cages with endohedral alcoholic functionality were found to have different binding properties than unfunctionalized analogs. Cages with introverted alcohol groups were also exploited for their ability to self-catalyze reactions on the interior of the hosts. The metal vertices themselves could also be used as functional groups, and showed the ability to sense neutral analytes in hybrid dative/hydrogen bonded self-assemblies.
7
Lee, Youn-Sik. "Supramolecular assemblies of polymerizable phospholipids." Diss., The University of Arizona, 1992. http://hdl.handle.net/10150/185929.
Full textAbstract:
Novel polymerizable ether lipids, 1,2-O-bis[10-(2',4'-hexadienoyloxy)decyl]-rac, 1,2-O-bis(10,12-tricosadiynyl)-rac, and (S)-2,3-O-bis(10,12-tricosadiynyl)-sn-glycero-1-phosphocholine (PC), were successfully synthesized. Differential scanning calorimetry (DSC) showed that the gel to liquid crystalline phase transition of the ether lipid bilayers occurs at 11.4, 27.6, and 30.0°C (T(m)), respectively. The T(m) of the saturated analogs of the sorbyl ether and ester lipids, which were synthesized for the study of lipid phase behavior, were -15.4 and -7.5°C, respectively. The sorbyl and diacetylenic ether lipids in bilayers were readily polymerized with 254 nm light. The stability of sorbyl either lipid vesicles toward a detergent, Triton X-100, was somewhat enhanced by photopolymerization. The optically active diacetylenic ether lipid formed microtubules and helices which were observed by transmission electron and optical microscopy. Polymerizable ester lipids, 1-palmitoyl-2-(2-methylene)palmitoyl, 1,2-bis(2-methylenepalmitoyl), and 1-oleoyl-2-(2-methylene)palmitoyl PC were synthesized. The T(m) of these lipids were estimated to be 33.6, 25.3, and ∼-10°C, respectively, via DSC and X-ray diffraction. Thermal reaction of the mono-substituted lipid suspensions with a water-soluble initiator, azobis(2-amidinopropane) dihydrochloride (AAPD), yielded oligomers which were soluble in organic solvents. However, reaction of the bis-substituted ester lipid in bilayers produced cross-linked polymers which are not soluble in organic solvents. The ceiling temperature for the radical polymerization of these lipid systems appears to be near 70°C since the polymerization conversion at 60°C was greater than at 70°C. Finally, a polymerizable ester lipid, 1-oleoyl-2-(2-methylene)palmitoyl-sn-glycerol-3-phosphoethanolamine (PE) was synthesized. According to DSC and X-ray diffraction, this hydrated PE suspension undergoes the transition from the lamellar liquid crystalline to the nonlamellar inverted hexagonal (H(II)) phase at 45-50°C. This compound (T(m) = 11.6°C) is a promising candidate for future studies of the stabilization of the H(II) phase.
8
Frankel, David Alan. "Supramolecular assemblies of diacetylenic amphiphiles." Diss., The University of Arizona, 1993. http://hdl.handle.net/10150/186384.
Full textAbstract:
Ever since the earliest studies, lipids have always been found in liposomal form. Recently, it was discovered that aqueous solutions of certain glycolipids, phospholipids, and glutamate lipids could form nonspherical morphologies such as tubules or helices when cooled below their liquid to gel phase transitions. We have developed new synthetic polymerizable lipids which form non-spheroidal morphologies when hydrated. The use of diacetylenes has several advantages which include facile incorporation into alkyl chains of amphiphiles, stabilization of assemblies, and the introduction of non-linear optical, and conducting properties into these assemblies. This research may also provide insight into the molecular basis of self-organization. Multistep synthesis of diacetylenic glycosurfactants was performed in which the headgroup was progressively varied by incorporation of different hepto, hexo, pento, and tetrose open chain sugars. The stereochemical, enantiomeric, and hydrophobic/hydrophilic balance of the lipids was investigated as a function of the supramolecular morphologies which they formed. Synthetic diacetylenic lipids based on a glutamic acid backbone were also prepared. These lipids formed liposomes which could be dehydrated under constant temperature and humidity to form cast films with properties similar to Langmuir-Blodgett films. These lipids could also be used as templates to order other compounds which do not otherwise form ordered assemblies. From the work we hope to gain some insight to the molecular components of lipids which are necessary to dictate specific supramolecular morphologies.
9
Lin, Xiang. "The supramolecular chemistry of metal-organic coordination oligomers and polymers." Thesis, University of Nottingham, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.416395.
Full text
10
Barker, Philip. "The introduction of supramolecular architectures into macromolecular arrays." Thesis, University of Warwick, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.250967.
Full text
11
Thompson, Alexander Martin Williams Cargill. "Transition metal-terpyridine complexes as supramolecular building blocks." Thesis, University of Cambridge, 1993. https://www.repository.cam.ac.uk/handle/1810/272557.
Full text
12
Wahl, Helene. "Development of novel supramolecular framework materials based on organic salts." Thesis, Stellenbosch : Stellenbosch University, 2014. http://hdl.handle.net/10019.1/95858.
Full textAbstract:
Thesis (PhD)--Stellenbosch University, 2014.ENGLISH ABSTRACT: The aim of the work presented in this thesis was to design ionic organic framework materials based on carboxylate salts with the intention of engineering interesting properties, such as porosity, into these framework materials. The first section focuses on the characterisation and porosity studies of an ionic framework material, 3,4-lutidinium pamoate hemihydrate, with THF-filled channels in the solid state. It was shown that this framework is able to exchange the THF in the channels for a wide variety of compounds, with many of these exchanges occurring in a single-crystal to single-crystal fashion. Competition experiments conducted with the framework, both by immersing crystals of the framework in solvent mixtures, as well as by exposing crystals of the framework to mixtures of solvent vapours, indicated that it is able to selectively exchange for one guest over another. The kinetics of exchange of this framework were studied, and it was possible to identify a kinetic model describing this process. A second novel framework-type material, 4-phenylpyridinium pamoate, was identified during the course of this study, as well as five isostructural frameworks containing different guest molecules. In this case the framework consists of discrete units that close-pack in such a way that guest molecules are included in constricted cavities in the solid state. Although this framework-type material is not porous, it is thermally quite stable and also highly selective. It is able to selectively encapsulate 1,4-dioxane when crystallised from various solvent combinations including 1,4-dioxane. In addition, eight novel structures with pamoic acid in combination with various pyridyl derivatives were obtained. A third novel framework material was obtained with N,N'-bis(glycinyl)pyromellitic diimide in which, due to the extended hydrogen-bonded network formed between the constituents of the framework, DMF molecules are aligned in channels. It was found that this framework material can also be formed by mechanochemical synthesis, and investigation of the thermal behaviour of this framework showed that it has the potential to be porous, since the framework appears to remain intact after desolvation. Furthermore, six novel structures with N,N'- bis(glycinyl)pyromellitic diimide in combination with various N-heterocycles were obtained. All structures obtained in this study were also further analysed to determine whether there are particular structural features that are required for framework formation. Insights gained from these investigations, in terms of degree of ionisation of the anion, packing arrangements and hydrogen bonding patterns as well as the molecular shape of the components are discussed.
AFRIKAANSE OPSOMMING: Die doel van die werk wat in hierdie tesis voorgelê word is om ioniese organiese raamwerkmateriale gebaseer op karboksilaatione te ontwerp, met die voorneme om interessante eienskappe in hierdie materiale te bewerkstellig. Die eerste afdeling fokus op die karakterisering en porositeit van ‘n ioniese organiese raamwerkmateriaal, 3,4-lutidiniumpamoaathemihidraat, wat kanale gevul met tetrahidrofuraan (THF) besit. Dit is aangetoon dat dit moontlik is vir hierdie raamwerkmateriaal om die THF in die kanale te verruil vir ‘n wye verskeidenheid stowwe, waarvan baie van hierdie uitruilings geskied as ‘n enkelkristal tot enkelkristal transformasie. Kompetisie-eksperimente is met hierdie raamwerkmateriaal uitgevoer deur die kristalle in mengsels van oplosmiddels te onderdompel, sowel as deur die kristalle aan mengsels van die oplosmiddeldampe bloot te stel. Die resultate het aangedui dat dit moontlik is vir hierdie raamwerkmateriaal om een gasstof selektief teenoor ‘n ander te verruil vir die THF in die kanale. Die kinetika van die uitruilingsproses van hierdie materiaal is ook bestudeer en dit was moontlik om ‘n kinetiese model te identifiseer wat die uitruilingsproses beskryf. ‘n Tweede nuwe raamwerk-tipe materiaal, 4-fenielpiridiniumpamoaat, is deur die loop van hierdie studie geïdentifiseer, sowel as vyf isostrukturele raamwerkmateriale waarvan net die gasstof verskil. In hierdie geval bestaan die raamwerk uit diskrete eenhede wat op so ‘n wyse saampak dat die gasstowwe in vernoude porieë ingesluit word. Alhoewel hierdie raamwerk-tipe materiaal nie poreus is nie, is dit termies stabiel en ook hoogs selektief. Die raamwerkmateriaal kan selektief 1,4-dioksaan enkapsuleer wanneer dit gekristalliseer word vanuit ‘n verskeidenheid oplosmiddel kombinasies met 1,4-dioksaan. Verder is agt nuwe strukture verkry met die pamoaat ioon in kombinasie met ‘n verskeidenheid piridien-derivate. ‘n Derde nuwe raamwerkmateriaal is verkry met N,N'-bis(glisiniel)piromellitiese diïmied waarin, danksy die uitgebreide waterstofgebinde netwerk tussen die komponente van die raamwerk, die DMF molekules in kanale aangetref word. Hierdie raamwerkmateriaal kan deur meganochemiese sintese berei word en verdere ondersoek na die termiese gedrag van hierdie raamwerkmateriaal dui aan dat dit die potensiaal het om porositeit te toon, aangesien die raamwerk behoue bly nadat die DMF molekules verwyder is. Ses nuwe strukture is ook met N,N'-bis(glisiniel)piromellitiese diïmied in kombinasie met ‘n wye verskeidenheid stikstof-bevattende heterosikliese verbindings verkry. Alle strukture wat tydens hierdie studie verkry is, is verder ondersoek om te bepaal of daar spesifieke strukturele kenmerke is wat benodig word vir die vorming van raamwerkmateriale. Insigte wat verkry is vanuit hierdie ondersoeke, in terme van die graad van ionisasie van die anioon, die rangskikking van molekules in die struktuur en waterstofbindingspatrone, sowel as die molekulêre vorm van die komponente, word bespreek.
13
Khemtong, Chalermchai. "Synthesis and Supramolecular Chemistry of 2,4,9-Trithiaadamantane Derivatives." University of Akron / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=akron1123084162.
Full text
14
Schultz, Anthony. "Design and Synthesis of Shape-persistent Terpyridine-based Matallomacromolecules and Architectures." University of Akron / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=akron1354651187.
Full text
15
Pearson, Jem M. "Hydrogen-bonding motifs for non-covalent synthesis." Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:f0630898-35b4-4c74-bc31-dfd252c2ee26.
Full textAbstract:
This work describes the design and synthesis of a set of four organic molecules that are intended to hydrogen-bond to each other in a pairwise manner. The four hydrogen-bonding units, termed ‘A’, ‘B’, ‘C’ and ‘D’, when placed in solution together, are designed so that A binds only to B, and C binds only to D. Each unit does not bind to itself, nor to either of the other two units to which binding is not intended. For example, A binds to B, but not to A, C, or D. Each unit contains an array of four hydrogen-bonds for strong binding to its partner, is designed to be as rigid as possible, as non-tautomeric as possible, and utilises a staggered non-symmetrical architecture. Of the four intended compounds, three were successfully synthesised (A, B and D). Units B and D were soluble in CDCl3, but Unit A was not. Therefore, the design and synthesis of Unit A was amended, and two variants of Unit A that are both soluble in CDCl3 were successfully synthesised. 1H NMR binding experiments were performed between Unit B and each of the two variants of Unit A. Their binding behaviour was described. A binding constant could not be calculated because the units did not bind in a 1:1 fashion.
16
Jin, Ping Atwood J. L. "Synthesis of mixed metal-organic pyrogallol[4]arene nanocapsules and their host-guest chemistry." Diss., Columbia, Mo. : University of Missouri--Columbia, 2009. http://hdl.handle.net/10355/6874.
Full textAbstract:
Title from PDF of title page (University of Missouri--Columbia, viewed on Feb 24, 2010). The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Dissertation advisor: Dr. Jerry L. Atwood. Vita. Includes bibliographical references.
17
Robertson, Craig Collumbine. "Building complex systems based on simple molecular architectures." Thesis, University of St Andrews, 2011. http://hdl.handle.net/10023/2573.
Full textAbstract:
Over the past twenty years molecules capable of templating their own synthesis, so called self–replicating molecules have gained prominence in the literature. We show herein that mixing the reagents for replicating molecules can produce a network of self–replicators which coexist and that the networks can be instructed by the addition of preformed template upon initiation of the reaction. Whilst self–replicating molecules offer the simplest form of replication, nature has evolved to utilise not minimal self–replication but reciprocal replication where one strand templates the formation of not an identical copy of itself but a reciprocal strand. Efforts thus far at producing a synthetic reciprocal replicating system are discussed and an alternative strategy to address the problems encountered is proposed and successfully implemented. The kinetic behaviour of a self–replicating reaction bears two distinctive time periods. Upon initiation, the reaction proceeds slowly as no template exists to catalyse the reaction. Upon production of the template, the reaction proceeds more rapidly via template direction. During this slow reaction period, the system is prone to mistakes as the reaction is slow and unselective. The creation of an [A•B] binary complex through non–covalent recognition of reagents allows for the reaction to proceed at an accelerated rate upon initiation however products of such a reaction are usually catalytically inert and do not promote further template directed reaction. A strategy to combine the desired behaviour of an [A•B] binary complex with the further template directed autocatalytic self–replicating reaction is described and implemented. Supramolecular polymers consist of repeating monomers which are held together by non–covalent interactions. The strong association of a self–replicating template dimer is comparable to that of supramolecular polymers reported thus far in the literature which are produced by cumbersome standard linear synthetic procedures. Herein the application of self–replication to the field of supramolecular polymer synthesis is discussed. As the autocatalytic reaction to produce the template monomers occurs under the same conditions as required to allow polymerisation to proceed, the polymer is able to spontaneously form in situ by self–replicating supramolecular polymerisation.
18
Lo, Pik Kwan Peggy. "Supramolecular DNA chemistry: assembly of DNA nanotubes and templated synthesis of DNA-mimetic polymers." Thesis, McGill University, 2010. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=95152.
Full textAbstract:
DNA has emerged as a promising template for the programmable assembly of structures on the nanometer scale. In particular, DNA nanotubes hold promise for a number of biological and materials applications, because of their high aspect ratio and encapsulation potential. Current construction methods result in symmetrical and cylindrical assemblies that are totally double-stranded, and are long and polydisperse. In order to investigate DNA nanotubes for applications as well-defined molecular hosts and one-dimensional templates, better control over their geometry, stiffness and porosity, ability to encapsulate and length needs to be achieved. Specifically, the first section of this thesis will describe (a) a modular approach to construct DNA nanotubes of geometrically well-defined triangular and square-shapes, which can exist in either double- and single-stranded forms with different stiffnesses, (b) the construction of DNA nanotubes with longitudinal variation by alternating larger and smaller capsules along the tube length, the encapsulation of guest molecules within these DNA nanotubes as well as their selective release with externally added DNA strands, (c) the use of a DNA-templated approach to produce nanotubes with controlled pre-determined lengths of 1 μm, and 500 nm and narrow length distributions, and the encapsulation of gold nanoparticles within these well-defined nanotubes to form finite lines of gold nanoparticles with longitudinal plasmon coupling. While DNA is a very promising construction material, it suffers from serious drawbacks for practical applications in materials science and biology. DNA is difficult and expensive to obtain in large quantities, and has limited long-term stability. On the other hand, synthetic polymers are routinely used as building blocks for nanostructured materials, with multiple applications in areas ranging from optics and data storage, to separation science and biology. Thus, an important challenge is the creation ofL'ADN s'est récemment manifesté comme un matériau prometteur pour l'assemblage programmable de structures à l'échelle nanométrique. En particulier, les nanotubes d'ADN sont intéressants pour leurs applications en science des matériaux et en biologie, en raison de leur aspect linéaire et leur potentiel d'encapsulation. Les méthodes courantes de leur synthèse produisent des assemblées symétriques et cylindriques totalement constituées de doubles brins d'ADN longs et polydisperses. Afin d'examiner les nanotubes d'ADN pour leurs applications comme des hôtes moléculaires à structure bien-définie et comme modèles unidimensionnels, des méthodes de synthèse qui mènent à un plus haut niveau de contrôle de leur géométrie, rigidité, porosité, capacité d'encapsulation et longueur doivent être développées. Plus précisément, la première section de cette thèse décrira (a) une approche modulaire pour construire des nanotubes d'ADN géométriquement bien définis, triangulaires ou carrés, et pouvant exister en formes d'ADN double-brin ou brin simple avec des différences de rigidité, (b) la construction des nanotubes d'ADN avec une variation longitudinale, en alternant les grandes et les petites capsules le long du tube, et l'encapsulation de matériaux invités au sein de ces nanotubes d'ADN, ainsi que leur libération sélective sous l'action de brins d'ADN externes ajoutés, (c) l'utilisation de l'approche d'un modèle d'ADN pour produire des nanotubes avec des longueurs contrôlées et prédéterminées de 1 µm ou de 500 nm et des distributions de longueurs étroites, et l'encapsulation de nanoparticules d'or au sein de ces nanotubes bien définis pour former des lignes de longueurs bien définies de nanoparticules d'or avec un couplage plasmonique longitudinal. Bien que l'ADN soit une molécule très intéressante pour l'auto-assemblage de structures, son utilisation comme un outil dans les applications pratiques en science des maté
19
Del, Valle Ian M. "Formation of Functionalized Supramolecular Metallo-organic Oligomers with Cucurbituril." Ohio University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1449233679.
Full text
20
Drager, Anthony Steven. "Synthesis and polymerization of supramolecular assemblies of octasubstituted phthalocyanines." Diss., The University of Arizona, 2001. http://hdl.handle.net/10150/279826.
Full textAbstract:
Substituted phthalocyanines (Pc's) are an important class of organic molecules, which have shown promise in the field of organo-electronics. The goal of the current research was to synthesize a new class of polymerizable Pc's. It was hoped that the new class of compounds would exhibit similar liquid crystalline and self organization properties that had been demonstrated by 2,3,9,10,16,17,23,24-octakis(2-benzyoxyethoxy) phthalocyanine. This Pc formed stable Langmuir monolayer and bilayers, which could be transferred to solid supports without losing the long-range order. The initial reactive Pc was 2,3,9,10,16,17,23,24-octakis(2-benzyoxyethoxy) phthalocyanine. The monomer was a beta-substituted styrene that was located within the alkoxy chains, to prevent inter-columnar cross-linking. The styrene functionalities were dimerized (35% reaction) by photolysis at 254 nm to form cyclo-butanes. The rod-like polymers were characterized using AFM and MALDI-TOF mass spectral analysis and the molecular rods obtained had a mean length of 72 nm. The styrylethoxy Pc was shown to be more crystalline then the previous benzyloxyethoxy Pc's, in order to correct this a new class of reactive Pc's were developed that contained a second oxygen atom. DSC data on the cinnamyloxyethoxy Pc shows that the lower temperature for the liquid crystalline mesophase was restored. Polymerization experiments performed on the cinnamyloxyethoxy Pc showed faster and 2x higher percent conversion. The research detailed in this dissertation describes a novel Diels-Alder synthetic approach to this important class of molecules and a new generic route to polymer rods of Pc.
21
Weingart, Jacob J. "Synthesis and Interfacial Chemistry of Supramolecular Assemblies." University of Akron / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=akron1289842486.
Full text
22
Meng, Wenjing. "Metal-organic polyhedra : subcomponent self-assembly, structural properties, host-guest behavior and system chemistry." Thesis, University of Cambridge, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.610719.
Full text
23
Ivasenko, Oleksandr. "Supramolecular design of hydrogen-bonded architectures via surface self-assembly of carboxylic building blocks." Thesis, McGill University, 2011. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=97007.
Full textAbstract:
Crystal engineering deals with the design of ordered arrays of molecular building blocks and is of high importance in nanotechnology, electronics and in the pharmaceutical industry. While organic synthesis provides access to a wide range of molecules, control over their intermolecular interactions is the major challenge taken on by crystal engineering. This thesis focuses on the surface self-assembly of carboxylic acids, as a convenient model system to study general factors governing self-assembly. It is a step towards the rational design of materials with desired compositions, morphologies and functionalities.Specifically, this thesis presents a systematic investigation of hydrogen-bonded (H-bonded) assemblies of carboxylic building blocks on surfaces (i.e. 2D crystals), complemented by studies of their assemblies in bulk solid state (i.e. 3D crystals). This work provides new insights into the complex relationship between building block structures, H-bonding synthons and self-assembly outcomes using scanning tunneling microscopy (STM), X-ray diffraction crystallography and quantum-mechanical calculations. Consideration of these insights has resulted in the supramolecular design of novel self-assembled molecular networks (SAMNs), described below.To elucidate the effect of building block structure on self-assembly, architectures formed by cyclic homo-dimers of carboxylic groups (i.e. structures containing the R22(8) synthon) are analyzed. Results are given in the form of case-studies covering formation of H-bonded macrocycles, chains, ladders, rotaxanes, catenanes and various 2D and 3D nets. Similar analyses of other H-bonding carboxylic acid assemblies are used to highlight the most important aspects of the carboxylic group's supramolecular reactivity, as well as the applications thereof.A detailed study of the surface co-assembly of trimesic acid (TMA) with n-alcohols is presented. Investigating this single system allows for the observation of a wide variety of phenomena that were previously only studied separately, and on structurally different systems. This enables relevant comparisons between molecular structure and the many factors governing self-assembly at the liquid-solid interface. The periodicity and fine structure of the TMA-alcohol SAMN is conveniently modulated by varying n-alcohol length and parity, representing an important step towards rational molecular nanopatterning of surfaces using the principles of crystal engineering.Relationships between building block structures and the stability of resulting carboxylic homosynthons (viz. the cyclic dimer R22(8), the trimer R33(12) and the hexamer R66(24)) are established through a combination of empirical observations and quantum-chemical calculations. Thus, formation of specific homosynthons is found to depend strongly upon steric intermolecular interactions, as well as upon the relative packing efficiencies of competing polymorphs. These findings allow explanation of the structure and chiral nature of the self-assembly formed by terthienobenzenetricarboxylic acid (TTBTA). Additionally, the rational design of supramolecular networks formed by the R66(24) homosynthon is demonstrated for the first time, using triethynylbenzenetricarboxylic acid (TEBTA).Finally, porous TMA networks are used as host matrices to control and study the self-assembly of new π-functional guest molecules. Specifically, two semiconducting heterocirculenes (sulflower and selenosulflower) are imaged by STM with sub-molecular resolution, enabling the study of adsorption-desorption dynamics, host-guest interactions, and stable π-π stacking architectures. The latter findings open up the possibility to form multilayers of host-guest architectures with high potential for applications in optoelectronic devices.L'ingénierie des cristaux de solides moléculaires est un domaine en plein essor, combinant de nombreux aspects de la chimie des matériaux. Il est d'une grande importance pour l'électronique, la nanotechnologie ainsi que pour l'industrie pharmaceutique, ou il y a grand besoin de concevoir des réseaux ordonnés de molécules. Alors que la synthèse organique donne accès à un grand éventail de molécules, le contrôle des interactions intermoléculaires entre celles-ci est le défi pris en charge par l'ingénierie des cristaux. Cette thèse se concentre sur l'auto-assemblage d'acides carboxyliques en surface, en utilisant ce dernier comme modèle pour étudier les facteurs généraux gouvernant l'auto-assemblage. Cette étude constitue une étape vers la conception rationnelle de matériaux ayant des compositions, morphologies et fonctionnalités tels que souhaitées.Plus précisément, cette thèse présente une étude systématique de l'assemblage de certains blocs carboxyliques en surface (i.e. des cristaux 2D), complétée par des études de leurs assemblées à l'état solide (i.e. des cristaux 3D). Ce travail apporte un nouvel éclairage sur la relation complexe entre la structures des blocs, des synthons liées par des ponts hydrogènes et l'auto-assemblage final. Cette étude met en oeuvre la microscopie à effet tunnel (STM), la cristallographie par diffraction des rayons-X et des calculs a base de mécanique quantique. La nouvelle compréhension établie par cette étude a permis d'aboutir à la conception de nouveaux réseaux moléculaires auto-assemblees (SAMNs), décrit ci-dessous.Pour élucider l'effet de la structure des blocs sur l'auto-assemblage, les architectures formées par des homo-dimères de groupes carboxyliques (c'est-a-dire par des structures contenant le synthon R22(8)) sont analysées. Les résultats sont donnés sous la forme d'études de cas, portant sur la formation de macrocycles (liées par des ponts hydrogènes), de chaînes, d'échelles, de rotaxanes, de caténanes et de divers filets en 2D et en 3D. Des analyses similaires d'autres ensembles d'acides carboxyliques sont utilisés pour mettre en évidence les aspects les plus importants de la réactivité supramoléculaire du groupe carboxylique, ainsi que de l'utilité de celle-ci.Une étude détaillée du co-assemblage de l'acide trimésique (TMA) avec des n-alcools est présenté. La recherche complétée sur ce système permet l'observation d'un grand éventail de phénomènes n'ayant été qu'étudiés séparément. Entre autre, cela permet des comparaisons pertinentes entre structure moléculaire et les nombreux facteurs qui régissent l'auto-assemblage à l'interface liquide-solide. La structure fine et la périodicité du SAMN TMA-alcool est modulée simplement, en faisant varier la longueur et la parité des n-alcools. Ceci représente une étape importante vers la nanostructurisation rationnelle des surfaces avec des molécules, en utilisant les principes de l'ingénierie des cristaux.Les relations entre les structures des blocs et la stabilité des homosynthons carboxyliques qui en resultent (à savoir le dimère cyclique R22(8), le trimère R33(12) et l'hexamère R66(24)) sont établies par une combinaison d'observations empiriques et de calculs émanant de la chimie quantique. Ainsi, la formation d'homosynthons spécifiques se trouve à dépendre fortement des interactions stériques intermoléculaires, ainsi que de l'efficacité relative des polymorphes qui résultent de l'assemblage. Ces résultats permettent l'explication de la structure et de la nature chirale de l'auto-assemblage formé par l'acide terthienobenzenetricarboxylic (TTBTA). En outre, la conception rationnelle des réseaux supramoléculaires formés par l'homosynthon R66(24) est démontré pour la première fois, a l'aide de l'acide triethynylbenzenetricarboxylic (TEBTA).Enfin, les réseaux poreux TMA sont utilisées comme matrices d'accueil pour contrôler et étudier l'auto-assemblage de nouvelles molécules π-fonctionnelles.
24
Auffray, Morgan. "Cyclophanes, a bridge between photophysics and supramolecular chemistry." Thesis, Paris 6, 2017. http://www.theses.fr/2017PA066285/document.
Full textAbstract:
Dans ce travail, des derivés du dithia[3.3]paracyclophane sont étudiés pour des applications en nanostructuration de surfaces et comme nouveaux fluorophores. Dans un premier temps, l'auto-assemblage supramoléculaire de molécules est utilisé pour créer des réseaux 2D sur surface. Cependant, l'utilisation de tels substrats a tendance à annihiler les propriétés électroniques des composés adsorbés. Par conséquent, des dérivés 3D du dithia[3.3]paracyclophane sont employées afin d'éloigner le composant actif de la surface. Dans cet optique, de nouvelles molécules à base de groupements pyridine ont été conçues pour s'auto-assembler sur différents substrats. Les caractérisations préliminaires ont été effectuées afin d'étudier les propriétés d'auto-assemblage de telles molécules seules ou co-adsorbées, et les premières images de réseaux 2D auto-organisés sur graphite et or ont été obtenues par microscopie à sonde locale. Dans un second temps, de nouveaux composés sont actuellement étudiés pour électroluminescence à haute rendement à partir de la fluorescence retardée à activation thermique (TADF). Ce phénomène est généralement observé pour des molécules montrant un faible gap électronique entre ses états excités singulet et triplet, lié au faible recouvrement des orbitales HOMO et LUMO localisées sur le donneur et l'accepteur, respectivement. Dans ce contexte, nous proposons un nouveau design de molécules de type donneur-accepteur où HOMO (donneur) et LUMO (accepteur) sont séparées par un cœur cyclophane. Nous avons synthétisé deux émetteurs et leurs propriétés photo-physiques ont été étudiées en solution et à l'état solideIn this work and due to their unique electronic properties, 3D-dithia[3.3]paracyclophane-based molecules have been studied for surface nanostructuration applications and as new fluorophore. First, the supramolecular self-assembly of molecules is used to create well-organised 2D-networks on conducting surfaces. However, the use of such substrates tends to quench any electronic properties of the adsorbed molecules. In this context, 3D-dithia[3.3]paracyclophane-based molecules were employed to lift up the active moiety from the surface. In this work, new pyridyl end-capped molecules were designed to self-assemble on any substrate. Preliminary characterisations were performed to study the supramolecular self-assembly of such molecules alone or with co-adsorbers, and the first images of organised 2D-networks on graphite and gold have been obtained by scanning probe microscopy. Second, the design of new and efficient emitter is a hot topic for the fabrication of OLED devices. A new type of compounds is currently investigated for their high electroluminescence efficiency due to thermally activated delayed fluorescence (TADF). This phenomenon is expected from molecules showing low electronic gap between singlet and triplet excited states, which is related to a low overlap of the HOMO and LUMO, localised on the electron-door and acceptor moieties of the molecule, respectively. In this sense, we propose a new design of donor-acceptor molecules where the HOMO (donor) and LUMO (acceptor) are separated by a cyclophane core. We synthesised a couple of emitters and their photophysics properties were studied in solution and in solid state
25
Boduroglu, Serhan. "New Supramolecular Approach for Sugar Analysis." University of Akron / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=akron1160147496.
Full text
26
Stojakovic, Jelena. "Supramolecular catalysis, discrete aromatic stacks and sequential reactions in the organic solid state." Diss., University of Iowa, 2014. https://ir.uiowa.edu/etd/4766.
Full textAbstract:
The organic solid state is becoming more widely utilized to synthesize molecules that are inaccessible or difficult to realize from the liquid phase. A solid-state synthesis provides strict control of both geometry and stereochemistry. While essential for efficient and sustainable organic syntheses, catalysis in the organic solid state is expected to be difficult to achieve due to low diffusion rates of molecules in the crystals. However, recently a ditopic receptor was used as a small-molecule supramolecular catalyst to direct a topochemical [2+2] photodimerization of an olefin. To achieve catalytic turnover, mechanochemistry, in the form of a manual mortar-and-pestle dry grinding, had to be employed. A main obstacle in the manual grinding method is the fact that the mechanochemistry and photoreaction are conducted separately. Thus, an automated method that enables simultaneous grinding and irradiation would be preferred. However, such technology is not commercially available. We have developed a simple, readily accessible, and automated method to achieve the mechanochemical preparation of supramolecular materials. Importantly, method enables simultaneous grinding and irradiation. In effect, the vortex grinding serves as a ball mill that is UV irradiation transparent. The vortex method has been applied to the preparation of cocrystal and metal organic frameworks, as well as supramolecular catalysis. When conducted using vortex method, supramolecular catalysis proceeds four time faster than when conducted using manual grinding. Accelerated rate of catalysis is attributed to combination of external stress exerted by grinding and internal stress arising from photoreaction.
The scope of supramolecular catalysis is expanded to reaction of 2,2'-bpe, catalyzed by a similar ditopic receptor res. Importantly, in this system catalytic turnover proceeds spontaneously. The mechanism of catalysis was investigated using X-ray diffraction studies and gas-phase DFT calculations. The studies uncovered that 2,2'-bpe and 2,2'-tpcb undergo rotational motion to release accumulated stress akin to action of a supramolecular torsional spring.
We report an integration of aromatic stacks into discrete assemblies based on hydrogen bonds in the solid state. We used indolo[2,3-a]carbazole to organize aromatics into double, triple, and quadruple stacks within cocrystals. We also showed that aromatics within quadruple stack undergo topochemical [2+2] photodimerization to give a single photoproduct stereoselectively in up to maximal yield.
We reveal the first example of a product of a templated solid-state that acts as a template in subsequent reaction. Both reactions proceed in 100% yield and stereoselectively. We also report the unique case of polymorphism where both polymorphs are photoreactive and within one polymorph photoreaction proceeds in SCSC manner.
Due to effects of crystal packing, homology in solid state is difficult to achieve. We present the application of the template screening approach to solid-state photoreactivity among all olefins of a homologous series. To assess electronic effects of substituents on stability and hydrogen bonds of assemblies, we preformed gas-phase DFT calculations on a series of substituted assemblies. We found, that the strength of hydrogen-bonding varies and correlates with electronic nature of the substituents.
Lastly, we incorporated principles of supramolecular chemistry, solid-state reactivity, green chemistry and sustainability in undergraduate curriculum. In particular, students employ supramolecular chemistry to control photoreactivity in the organic solid state using the template approach. To form supramolecular assemblies, mechanochemistry, in form of mortar-and-pestle grinding, is used. To study reactivity in crystals, X-ray diffraction is used. Students are involved in all steps necessary to obtain crystal structure: growing suitable crystals, selection of the best crystals, data collection, solution, refinement and analysis of the crystal structures. Overall, students have hands-down experience in all aspects of crystallography. Although essential in chemical, biochemical, pharmaceutical and materials science, crystallography is rarely taught in undergraduates laboratories.
27
Sprafke, Johannes Klaus. "Supramolecular control of synthesis and electronic structure of porphyrin oligomers." Thesis, University of Oxford, 2011. http://ora.ox.ac.uk/objects/uuid:520bfa69-8cd5-4615-96fb-487651dd557a.
Full textAbstract:
The work described in this thesis demonstrates the use of supramolecular chemistry in the template-directed synthesis of porphyrin nanorings and as a tool to control conformation and topology of π-conjugated porphyrin oligomers. Particular emphasis is placed on changes to the electronic structure of these oligomers depending on their conformation. Chapter 1 gives an overview of π-conjugated porphyrin oligomers and conjugated macrocycles in general, followed by an introduction into supramolecular cooperativity and small angle X-ray scattering in solution. Chapter 2 describes advances in the synthesis, solution structure elucidation and optoelectronic properties of a fully conjugated cyclic porphyrin hexamer. The high rigidity and symmetry of this nanoring as well as its bent π-system lead to a significant decrease in its HOMO-LUMO gap. The resulting near-infrared emission was exploited in the fabrication of light emitting diodes, demonstrating the use of a bent topology for minimizing aggregation in thin films. The synthesis of a [12]porphyrin nanoring using a hexadentate template is presented in Chapter 3. The concept of Vernier templating is introduced as a general strategy for the synthesis of large monodisperse macrocycles. The nanoring is characterized and its cooperative binding to two template molecules is studied. In Chapter 4 a bidentate ligand is used in the cooperative formation of a sandwich complex beween two nanorings. Chapter 5 provides an analysis of the rigidity of the butadiyne linked porphyrin oligomers used throughout this thesis. A linear chain is significantly more flexible in solution than on a surface where it is confined within two dimensions. Analysis of the persistence length indicates that a porphyrin nanoring with more than around 20 units would not be significantly strained. The supramolecular binding of linear porphyrin oligomers to carbon nanotubes is analyzed in Chapter 6. The binding strength increases sharply with oligomer length and binding is strongest with (8,6) and (7,5) tubes. The energy level alignment in these porphyrin CNT complexes appears to be favorable for an application in photovoltaics. In Chapter 7 bisamidine-carboxylate salt bridges together with zinc-nitrogen coordination chemistry are used to access a variety of topologies in assemblies based on carboxylic acid functionalized porphyrin dimers.
28
Cangelosi, Virginia May 1982. "Supramolecular coordination chemistry of phosphorus, arsenic, antimony, and bismuth with organothiolates." Thesis, University of Oregon, 2010. http://hdl.handle.net/1794/11301.
Full textAbstract:
xxiv, 203 p. : ill. (some col.) A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number.The ever-expanding field of supramolecular chemistry has recently incorporated use of the main group ions. This dissertation presents a supramolecular approach to the coordination chemistry of the Group 15 elements, with a special emphasis on arsenic (As). Arsenic is ubiquitous in our environment, contaminates the drinking water of large human populations, and is a worldwide health concern. Arsenic's legendary toxicity is thought to be due to its thiophilicity and the stability of arsenic-thiolate bonds within proteins. Chapter I is a review of the current literature on the kinetics, thermodynamics, and supramolecular chemistry of the As(III)-thiolate bond and reveals that the stability and lability of the bond make it well-suited for supramolecular chemistry. The remainder of the dissertation explains our supramolecular design strategies for the As(III) ion with thiolate ligands, then expands the approach to the Group 15 elements phosphorus, antimony, and bismuth. Chapter II presents an approach to controlling diastereoselectivity in the self-assembly of supramolecular As 2 L 2 Cl 2 macrocycles using intramolecular steric interactions. Chapter III expands upon this approach by using intermolecular steric interactions to control diastereoselectivity and dimer formation of As 2 L 2 Cl 2 macrocycles. Chapter IV gives insight into the self-assembly of these As 2 L 2 Cl 2 macrocycles by identifying several reaction intermediates and kinetic mistakes that form during the course of the reaction. In Chapter V the application of our design strategy to the heavier Group 15 elements of antimony and bismuth is shown through the presentation of E 2 L 3 cryptands (E = As, Sb, Bi). Additionally, a Group 15 "transmetallation" reaction is explained which allows, for the first time, the preparation of the elusive P 2 L 3 cryptand. Chapter VI further examines the transmetallation reaction, the solution isomerism of the E 2 L 3 cryptands, and presents three heterometallic EE'L 3 cryptands. Finally, Chapter VII briefly concludes this dissertation and provides some potential future directions for the project. This dissertation includes co-authored material and previously published results.
Committee in charge: James Hutchison, Chairperson, Chemistry; Darren Johnson, Member, Chemistry; Catherine Page, Member, Chemistry; Michael Haley, Member, Chemistry; Scott Bridgham, Outside Member, Biology
29
D'Souza, Lawrence Joseph. "Bile Acid Based Molecular Tweezers And Crown Ethers." Thesis, Indian Institute of Science, 1995. http://hdl.handle.net/2005/114.
Full textAbstract:
Chapter 1. Introduction to Molecular Tweezers
Whitlock and Zimmerman developed a class of molecular hosts, popularly known as molecular tweezers, which sandwich aromatic guests by ii=ii interaction. Chapter 1 summarizes molecular tweezers of various kinds which have recently been synthesized.
Chapter 2. Design and synthesis of "Bile Acid-Based Molecular Tweezers" Bile acids have a rigid backbone, and the array of hydroxyl groups separated by 5-7 A provides opportunities for the attachment of binding surfaces such as two extended chromophoric units.
30
Lifshits, Liubov Mikhaylovna. "A supramolecular approach for engineering functional solid-state chromophore arrays within metal-organic materials." Bowling Green State University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1460155929.
Full text
31
Bucar, Dejan-Kresimir. "Crystal engineering of organic and metal-organic solids: design, structure and properties." Diss., University of Iowa, 2010. https://ir.uiowa.edu/etd/3435.
Full textAbstract:
Crystal engineering has recently emerged as a method of choice for the design and the construction of functional materials. Solid-state synthesis, of the most commonly studied aspects of crystal engineering, has been shown to provide access to molecular targets that are hardly obtainable using principles of conventional (i.e. solution-based) organic synthesis. Reactions in the solid state are, however, not routinely used in organic synthetic chemistry. The scarce use of solid-state reactions can be attributed to the difficulty of predicting molecular arrangements in the solid state, as well as to the lack of methodologies to control crystal packing. Template-directed solid-state synthesis is a recently developed modus operandi that enables control over reactivity within multi-component crystals. The thesis is focused on the application of template-directed solid-state approach to [2+2] photocycloaddition reactions in the solid state, as well as on the understanding of intermolecular interactions in crystals. Synthetic templates have been utilized to construct cocrystals that enable a class of hitherto underdeveloped organic solid-state reactions, namely [2+2] cross-photoaddition reactions. In addition, products derived form templated solid state reactions, namely tetrapyridylcyclobutanes, have been utilized to generate exceptional materials, such as thixothropic hydrogels based on nano-dimensional metal-organic particles. The utility of crystal engineering has also been expanded to the nanoscience and the development of nanomaterials. A crystallization method for the preparation of nano-dimensional cocrystals has been developed. The method has been shown to enable single-crystal-to-single-crystal [2+2] photodimerizations of olefins. In addition, nano-dimensional cocrystals have been shown to exhibit distinctive mechanical properties upon single-crystal-to-single-crystal transformations.
In addition to solid-state reactions and materials derived therefrom, we systematically studied hierarchies of supramolecular synthons in pharmaceutical cocrystals comprised of multi-functional molecules. Pharmaceutical cocrystals have been recently shown to exhibit physical properties superior to those of parent drugs. Our studies involved xanthine alkaloids as pharmaceutical agents and a series of hydroxylated benzoic acids as cocrystal formers. Synthon hierarchies have been established for three xanthine alkaloids. We also discovered pharmaceutical salts that formed where cocrystallization was expected to occur. Reasons contributing to such unexpected salt formation were investigated using X-ray crystallography and computational methods. The established synthon hierarchies are expected to contribute to a better understanding of self-assembly processes in cocrystals that is crucial for the development of state-of-art drugs, and the design of organic reactions in the solid state.
32
Bis, Joanna A. "Crystal engineering of organic compounds including pharmaceuticals." [Tampa, Fla] : University of South Florida, 2006. http://purl.fcla.edu/usf/dc/et/SFE0001424.
Full text
33
Buerkle, Lauren Elizabeth. "Tailoring the Properties of Supramolecular Gels." Case Western Reserve University School of Graduate Studies / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=case1317946752.
Full text
34
Chu, Cheng-Che. "Hydrogen-bonded supramolecular materials for organic photovoltaic applications." Thesis, Bordeaux 1, 2009. http://www.theses.fr/2009BOR13866/document.
Full textAbstract:
Dans ce manuscrit est décrite l'utilisation d'interactions supramoléculaires pour diriger l'auto-assemblage de composés donneurs et accepteurs d'électrons au sein de dispositifs photovoltaïques organiques. Dans ce but, des matériaux de type oligo-3-hexylthiophène et fullerène ont été fonctionnalisés avec des groupements de reconnaissance complémentaires mélamine – acide barbiturique. La présence de élements solubilisants confère à ces composés une bonne mise en oeuvre permettant la fabrication de dispositifs photovoltaïques à hétérojonction volumique. L'effet de la composition et du post-traitement de la couche active sur la performance de ces dispositifs ont été explorés. Les études de mobilité de charge et des mécanismes de recombinaison au sein de ces matériaux indiquent que l'équilibre entre auto-association et séparation de phases est crucial pour l'efficacité en conversion photovoltaïqueThis research aims to elucidate the use of supramolecular interaction to guide the formation of well-defined nanoscale self-assembled architecture in photovoltaic solar cells as a means to improve device efficiency. Complementary molecular recognition sites based on melamine and barbituric acid were used to obtain functionalized fullerene and oligothiophene materials with superior processibility thanks to the presence of specific solubilizing groups. The efficiency of solid-state devices fabricated using the bulk heterojunction design was studied with respect to device morphology and composition. Experiments on recombination mechanism and field effect mobilities suggest that the balance between hydrogen-bonding interactions induce self-assembly and p-p interactions to promote phase segregation is crucial to the micro-structure of the active layer. The investigated of the relationship between the oligothiophene chain size and various complementary hydrogen-bonding motifs is envisaged
35
Nkrumah, Anna. "Design, Synthesis, and Characterization of Dynamic Metallo-Supramolecular Polymers Stabilized by Non-Covalent Interactions." Ohio University Honors Tutorial College / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=ouhonors1369141489.
Full text
36
Scott, Benjamin M. T. "From small molecules to nano-scale architectures - a supramolecular approach." Diss., Manhattan, Kan. : Kansas State University, 2008. http://hdl.handle.net/2097/612.
Full text
37
Forbes, Safiyyah. "Hydrogen-bond driven supramolecular chemistry for modulating physical properties of pharmaceutical compounds." Diss., Manhattan, Kan. : Kansas State University, 2010. http://hdl.handle.net/2097/3756.
Full text
38
Elbatal, Hany. "Terpyridine-Based Metallo-Supramolecular Architectures: From Structure to Function." University of Akron / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=akron1384367887.
Full text
39
Rajbanshi, Arbin. "Supramolecular interactions from small-molecule selectivity to molecular capsules." Diss., Manhattan, Kan. : Kansas State University, 2010. http://hdl.handle.net/2097/3879.
Full text
40
Webre, Whitney Ann. "Spectral, Electrochemical, Electron Transfer, and Photoelectrochemical Studies of Tetrapyrrole Derived Supramolecular Systems." Thesis, University of North Texas, 2019. https://digital.library.unt.edu/ark:/67531/metadc1609091/.
Full textAbstract:
Energy- and electron-transfer processes in molecular and supramolecular donor-acceptor systems are of current interest in order to develop light-energy harvesting systems through designing covalently linked donor-acceptor systems or utilizing self-assembled donor-acceptor systems. The research presented in this dissertation deals with the electrochemical, anion binding, and photochemical studies of various oxoporphyrinogen (OxPs), porphyrin, corrole, and phenothiazine systems. The first chapter provides a brief introduction to the material discussed in the subsequent chapters. The second chapter discusses the bromination of meso-tetraarylporphyrings and how that affects their electrochemical, catalytic, and other properties. Bromination of these porphyrins and oxoporphyrinogens allow the HOMO-LUMO gap to increase revealing blue-shifted absorption. Brominated OxPs and bis-crown ether OxP self-assembled with anions depending on strength of the anion and size of the binding site. The addition of crown ethers allows a cation binding site which makes a self-assembled donor-acceptor supramolecular system.Chapters 5 and 6 discuss a series of donor-acceptor conjugates based on zinc porphyrin as the electron donor and copper(III) corrole as the electron acceptor. These studies illustrate the importance of copper(III) corrole as a potent electron acceptor for the construction of energy harvesting model compounds, and constitute the first definitive proof of charge separation in ZnP-CuIIIC systems.Chapter 7 summarizes several interesting observations made in the present study on DSSCs built on two types of phenothiazine dyes having one or two cyanocinnamic acid groups.
41
Toom, Lauri. "Bispidine Derivatives : Synthesis and Interactions with Lewis Acids." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Universitetsbiblioteket [distributör], 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-6735.
Full text
42
Dutta, Saikat. "Solid-state reactions in co-crystals: applications in synthetic chemistry and materials science." Diss., University of Iowa, 2010. https://ir.uiowa.edu/etd/491.
Full textAbstract:
Chemistry is on the verge of a new era where the attention of chemists has shifted from covalent bonds to noncovalent interactions and their use as a predictable way to guide reactions pathways and product formation. Nature synthesizes elegant molecules under mild conditions and the designed syntheses have been demonstrated to be largely dependent on recognition, self-assembly and templating effects between molecular building blocks. Although covalent synthesis in fluidic medium via supramolecular control has been achieved with limited success, organic solid state has been of particular interest since it avoids solvent effects, and is able to provide unique materials with remarkable stereoselectivity under environment-friendly conditions. Although reactions in solids have resulted in a number of remarkable discoveries in chemistry and materials science, solid-state synthesis is generally not considered as a mainstream synthetic medium and solid-state reactions are seldom appreciated as an efficient way to access molecular targets. Owing to the limited number of solid-state reactions and the uncontrollable nature of crystal packing, solid state has not been utilized readily as a primary synthetic medium. In this context, reactions conducted in multicomponent molecular assemblies or co-crystals have been attracting much attraction in recent years as a general way of controlling the reactivity of molecules in solid state. A molecular component in the multicomponent molecular solid, acting as a linear template, has been shown to preorganize molecules in a modular way via intermolecular interactions and engineer their physical and/or chemical properties. The [2+2]photodimerization of olefins is a successful demonstration how templated solid state synthesis can efficiently synthesize complex targets that are synthetically challenging via conventional routes. In this dissertation, the generality and synthetic applicability of the templated synthetic approach in solid state will be described. How supramolecular interactions in molecular co-crystals precisely guide covalent bond formation in order to construct complex molecular targets will be demonstrated. Finally, co-crystallization will be shown as a general way to control optical properties in crystals.
43
Ivy, Joshua F. "Optoelectronically Active Metal-Inorganic Frameworks and Supramolecular Extended Solids." Thesis, University of North Texas, 2018. https://digital.library.unt.edu/ark:/67531/metadc1248495/.
Full textAbstract:
Metal-organic frameworks (MOFs) have been intensely researched over the past 20 years. In this dissertation, metal-inorganic frameworks (MIFs), a new class of porous and nonporous materials using inorganic complexes as linkers, in lieu of traditional organic linkers in MOFs is reported. Besides novel MIF regimes, the previously described fluorous MOF "FMOF-1", is re-categorized herein as "F-MIF1". F-MIF-1 is comprised of [Ag4Tz6]2- (Tz = 3,5-bis-trifluoromethyl-1,2,4-triazolate) inorganic clusters connected by 3-coordinate Ag+ metal centers. Chapter 2 describes isosteric heat of adsorption studies of F-MIF1 for CO2 at near ambient temperatures, suggesting promise for carbon capture and storage. We then successfully exchanged some of these Ag(I) centers with Au(I) to form an isostructural Au/F-MIF1. Other, nonporous MIFs have been synthesized using Ag2Tz2 clusters with bridging diamine linkers 4,4'-bipyridine, pyrazine, and a Pt(II) complex containing two oppositely-situated non-coordinating pyridines. This strategy attained luminescent products better-positioned for photonic devices than porous materials due to greater exciton density.
Chapter 3 overviews work using an entirely inorganic luminescent complex, [Pt2(P2O5)4]4- (a.k.a. "PtPOP") to form new carbon-free MIFs. PtPOP is highly luminescent in solution, but as a solid shows poor quantum yield (QY ~0.02) and poor stability under ambient conditions. By complexing PtPOP to various metals, we have shown a dramatic enhancement in its solid-state luminescence (by an order of magnitude) and stability (from day to year scale). One embodiment (MIF-1) demonstrates microporous character.
Chapter 4 overviews the design and application of new MIF linkers. Pt complexes based upon (pyridyl)azolates, functionalized with carboxylic acid groups, have been synthesized. These complexes, and their esterized precursors, show strong luminescence on their own. They have been used to generate new luminescent MIFs. Such new MIFs may be useful toward future inorganic (LEDs) or organic (OLEDs) light-emitting diodes, respectively. The electronic communication along their infinite coordination structures is desirable for color tuning and enhanced conductivity functions, compared to the small molecules used in such technologies, which rely on intermolecular interactions for these functions.
44
Border, Sarah Elaine Border. "Light Responsive Molecular Baskets." The Ohio State University, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=osu1543329849092005.
Full text
45
Riba, Moliner Marta. "Supramolecular Strategies to Control the Assembly of Organic-Based Materials." Doctoral thesis, Universitat de Barcelona, 2015. http://hdl.handle.net/10803/378647.
Full textAbstract:
The focus of this thesis is the use of supramolecular chemistry to functionalize polymers to obtain organic-based materials with a control of their structure and properties.
The non-covalent functionalization of polymers via supramolecular chemistry is a potentially efficient route to introduce a particular property with which a new functional molecular material can be originated. This strategy has specially been explored to incorporate conjugated structures in polymeric constructs for new semiconducting materials. Although important advances have been made in this field, the incorporation of π-electron functional units to polymeric backbones with well-controlled arrangement between the donor and acceptor parts is still an area of huge interest for material science.
Following this idea, the supramolecular functionalization of the homopolymer poly(4-vinyl pyridine) (P4VP) with an electron donating unit based on an tetrathiafulvalene (TTF) has been explored. Tetrathiafulvalenes (TTFs) are excellent π-electron donor units that are widely studied in molecular electronic applications due to their p-type character and stable doped states. Through complementary hydrogen bonding components of a derivative TTF (TTFCOOH), uniform films incorporating the redox active components have been prepared. When the films were doped using different oxidising agents, Electrostatic Force Microscopy (EFM) studies indicated that a reorganisation at the surface of the films occurred and of charges in their surfaces appeared.
Once the application of the P4VP-TTFCOOH films as charge-carrier hybrid material was demonstrated, the next step was to use the block copolymer poly(styrene-b-4-vinyl pyridine) (PS-b-P4VP) due to its amphiphilic behavior. Therefore, different molar ratios of PS and P4VP blocks have been used to prepare new PS-b-P4VP-TTFCOOH thin films. The influence of the phase segregation of the PS-b-P4VP-TTFCOOH film to the charge transportation upon oxidation was performed correlating the Small-Angle X-ray Scattering (SAXS) and EFM results.
On the other hand, microfluidics is a microfabrication technique that relies on the manipulation of fluids, which can be used to control the final microstructure and self-assembly of compounds, by the simple adjusting of the values of the hydrodynamic flow focusing (confinement effect). Moreover, microfluidics offers respect to the bulk conditions important advantages such as larger relation surface-to-volume, lower consumption values and a better control of the concentration gradients. The improvement of the intermolecular contact of disk-shaped C3-symmetric tris(TTF) system has been studied using microfluidics. This molecule possesses three bonded derivative TTF units through a central aromatic ring that, under determined conditions, large coiled helical fibers could be obtained by their aggregation. A de-doping process of the C3-symmetric tris(TTF) molecule has been studied using microfluidics, towards the study of the influence of the technique on the organization of this compound. Afterwards, a new characterization methodology was suggested, based on bimodal-Atomic Force Microscopy (bimodal-AFM) in order to draw a distinction between electrostatic and mechanical contributions of the coiled fibers and, corroborating that the charge transportation phenomenon occurred.
Furthermore, hydrogels have been in the spotlight due to their biocompatibility in, for instance, tissue engineering applications. Then, the structural enhancement of an ionically-driven coacervated hydrogel obtained via microfluidics platform by tuning flow focusing parameters was studied. In a further step, the functionalization of this hydrogel with TTFCOOH molecules under bulk and microfluidic conditions and its charge-carrier character were also analyzed. Additionally, with the objective to immobilize the hydrogel on surfaces, micro-contact printing, technique was tested.
Finally, the organization and phase segregation of the PS-b-P4VP coordinated with a metalloporphyrin system has also been approached. Porphyrins, in general, possess exceptional inherent optical and electronic properties that make them suitable for application related with solar cells. Moreover, due to their electrochemical and photophysic characteristics they can easily be modified with other functional groups. Porphyrins can be found free or complexed with metals and in both states they have self-assembly properties. The coordination between PS-b-P4VP and chiral and an achiral zinc (II) metalloporphyrin has been explored in order to study the chirality transfer from the porphyrin to the hybrid materials. In the last instance, and in an exploratory attempt to use porphyrins as molecular rotors, different strategies of surface immobilization of the porphyrin-block copolymer system were also approached by micro-contact printing.
46
Schultheiss, Nathan C. "Balancing intermolecular interactions in the design and synthesis of supermolecules." Diss., Manhattan, Kan. : Kansas State University, 2007. http://hdl.handle.net/2097/264.
Full text
47
Kondratiuk, Dmitry. "Synthesis and properties of giant porphyrin nanorings." Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:73c76c1a-2124-4bb8-91a1-893f841a80a1.
Full textAbstract:
Fully conjugated porphyrin nanorings combine an end-free π-system with well defined size and shape. They provide models for testing our understanding of light harvesting in natural photosynthetic systems, and may lead to the creation of new functional materials. This thesis describes the template-directed synthesis of novel 10, 16, 18, 20, 24, 30, 40 and 50-porphyrin nanorings using small templates, as well as the investigation of their structure, electronic properties and supramolecular chemistry in solution and on surfaces. This work illustrates the scope of Vernier templating as a tool for the synthesis of monodisperse molecules of unprecedented sizes. Chapter 1 introduces key properties of porphyrins and π-conjugated linear and cyclic porphyrin oligomers and describes the principle methods of preparing non-conjugated and conjugated cyclic polymers. It also covers recent advances in the synthesis of fully-conjugated porphyrin nanorings, in particular Vernier templating. Chapter 2 discusses the formation of higher order porphyrin nanorings (18- and 24-porphyrin nanorings) in the classical synthesis of 6-porphyrin nanoring and the Vernier-templated synthesis of 12-porphyrin nanoring. Chapter 3 describes the Vernier-templated synthesis of 24-porphyrin nanoring and its characterization. Chapter 4 shows that the flexibility of 24-porphyrin nanoring can be locked by the formation of a “sandwich” complex in the presence of a bidentate ligand or by solvent-induced formation of aggregates. Chapter 5 demonstrates the use of templates to control the cyclooligomerization of linear porphyrin oligomers. Vernier-templated synthetic routes to 10-, 30- and 40-porphyrin nanorings are investigated. Chapter 6 reports the electronic properties of porphyrin nanorings as probed by electrochemistry (for 6 porphyrin nanoring) or fluorescence anisotropy measurements (for 24 porphyrin nanoring). Crystal structures of 6 and 12 porphyrin nanoring template complexes are presented. Chapter 7 contains experimental procedures and characterization data of known and novel compounds synthesized in the course of this thesis.
48
Pally, Nitin Kumar. "Synthesis and Structures of New Three-Dimensional Copper Metal-Organic Frameworks." TopSCHOLAR®, 2013. http://digitalcommons.wku.edu/theses/1295.
Full textAbstract:
Metal-organic frameworks (MOFs) are crystalline materials with metal ions covalently bonded to organic ligands. The ligands act as spacers often creating a porous structure with very high pore volume and surface area. MOFs are known for their robust structures, high porosity, and different chemical functionalities and are considered for applications in adsorptions, separations, catalysis and gas storage. This work focuses on the synthesis of new MOFs using copper compounds. Different types of carboxylate ligands were used for the synthesis. Two new copper-organic frameworks, [Cu3(pyz)(btc)] (1), and [(Cu3(btc))•xH2O] (2) (btc= benzene-1,3,5-tricarboxylate, pyz= pyrazine) have been synthesized using hydro/solvothermal methods and have been characterized using X-ray diffraction, IR, TGA, fluorescence and CHN analysis.
49
Wood, Evan A. "Designing hypercyclic replicating networks." Thesis, University of St Andrews, 2007. http://hdl.handle.net/10023/360.
Full textAbstract:
In the last 20 years there has been a number of synthetic and natural product based molecular replicators published in the literature. The majority of these systems have focused on the minimal model with only a few examples of cross-catalytic or reciprocal replication. Of the cross-catalytic systems investigated the majority focus around the use of natural products, oligonucleotides, peptides etc. This thesis will investigate the design, synthesis and kinetic analysis of both synthetic minimal and reciprocal replicating systems, and how these two forms of replication interact in a complex hypercyclic network. Chapter 1 introduces key concepts such as molecular recognition, intramolecularity/ enzyme kinetic, bisubstrate systems and the work conducted into replication systems to date. Chapter 2 describes the design, synthesis and kinetic analysis of a reciprocal replicating system, based on Diels-Alder and 1,3-dipolar cycloadditions, before going on to discuss what we have learned and how this system can be improved. Chapter 3 focuses on the design, synthesis and kinetic analysis of a replicating network (minimal and reciprocal replication), based on 1,3-dipolar cycloadditions. Initial individual systems are examined in isolation to determine their behavior and nature. After which the systems are combined to observe how each species interacts in a potential complex hypercyclic network. Chapter 4 investigates the redesign of the replicating network in Chapter 3 in order to overcome the problems identified from its kinetic analysis. Chapter 5 introduces the shift in direction away from kinetically controlled replicating networks towards systems in thermodynamic equilibrium.
50
Coskun, Ali. "Ion Sensing And Molecular Logic In Supramolecular Systems." Phd thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/2/12608736/index.pdf.
Full textAbstract:
Supramolecular chemistry is an emerging field of chemistry which has attracted much attention in recent years as a result of its broad applicability in many areas. Thus, the design of functional supramolecular systems is strongly in demand in this field. For this purpose, we have developed ratiometric fluorescent chemosensors for ion sensing and mechanically interlocked structures for their application in molecular logic.
In the first part, we report a novel dimeric boradiazaindacene dye which can be converted in one step to an efficient resonance energy transfer (RET) dyad. In addition, if this modification is done with appropriate ligands, RET can be coupled to ion sensing. The utility of this approach is demonstrated in a highly selective, emission ratiometric chemosensor for Ag(I).
In the second part, boradiazaindacene dyads designed as energy transfer casettes were modified to signal cation concentrations ratiometrically. If the energy transfer efficiency is increased by changing spectral overlap on cation binding, an enhancement of emission signal ratios can be obtained. A larger range of ratios results in highly improved sensitivity to analyte concentrations. We demonstrate this approach in a de novo design of a novel and highly selective ratiometric chemosensor for Hg(II) ions.
In the last part, we synthesized a two-station [2]catenane composed of an π
-electron rich bis-1,5-dihydroxynapthalene[38]-crown-10 (1/5DNPC10) ring interlocked with a second macrocycle containing two &
#960
-electron deficient unit, namely, napthodiimide (NpI) and bipyridinium (BIPY)2+ unit using the Cu(I)-catalyzed Huisgen 1,3-cycloaddition reaction. The resulting bistable [2]catenane is isolated as a single co-conformation which is comprised of the 1/5DNP[38]C10 ring around the NpI unit. Thermal activation of the pure NpI-isomer at 70&
#730
C for 60 h leads to the formation of the BIPY2+-isomer by virtue of the circumrotation of the crown-ether ring along the backbone of the other macrocycle over the steric barrier of the tetra-aryl methane units. The energy barrier for the circumrotation is 28.5±
0.3 kcal/mol. Electrochemistry of a 1:1 mixture of the two possible isomers shows that the [2]catenane cannot be switched mechanically on account of the large steric barriers presented by the tetra-aryl methane groups on the electron-accepting ring.