Polymer electrolytes are indispensable in numerous electrochemical systems. Existing polymer electrolytes rarely meet all technical demands by their applications (e.g., high ionic conductivity and good mechanical strength), and new types of polymer electrolytes continue to be developed. In this dissertation, the molecular structure and dynamics of three emerging types of polymer electrolytes featuring Coulombic liquids, i.e., polymerized ionic liquids (polyILs), nanoscale ionic materials (NIMs), and polymeric ion gels, were investigated using molecular dynamics (MD) simulations to help guide their rational design. First, the molecular structure and dynamics of a prototypical polyILs, i.e., poly(1-butyl-3-vinylimidazolium hexafluorophosphate), supported on neutral and charged quartz substrates were investigated. It was found that the structure of the interfacial polyILs is affected by the surface charge on the substrate and deviates greatly from that in bulk. The mobile anions at the polyIL-substrate interfaces diffuse mainly by intra-chain hopping, similar to that in bulk polyILs. However, the diffusion rate of the interfacial mobile anions is much slower than that in bulk due to the slower decay of their association with neighboring polymerized cations. Second, the structure and dynamics of polymeric canopies in the modeling NIMs where the canopy thickness is much smaller than their host nanoparticle were studied. Without added electrolyte ions, the polymeric canopies are strongly adsorbed on the solid substrate but maintain modest in-plane mobility. When electrolyte ion pairs are added, the added counter-ions exchange with the polymeric canopies adsorbed on the charged substrate. However, the number of the adsorbed electrolyte counter-ions exceeds the number of desorbed polymeric canopies, which leads to an overscreening of the substrate's charge. The desorbed polymers can rapidly exchange with the polymers grafted electrostatically on the substrate. Finally, the molecular structure and dynamics of an ion gel consisting of PBDT polyanions and room-temperature ionic liquids (RTIL) were studied. First, a semi-coarse-grained model was developed to investigate the packing and dynamics of the ions in this ion gel. Ions in the interstitial space between polyanions exhibit distinct ordering, which suggests the formation of a long-range electrostatic network in the ion gel. The dynamics of ions slow down compared to that in bulk due to the association of the counter-ions with the polyanions' sulfonate groups. Next, the RTIL-mediated interactions between charged nanorods were studied. It was discovered that effective rod-rod interaction energy oscillates with rod-rod spacing due to the interference between the space charge near each rod as the two rods approach each other. To separate two rods initially positioned at the principal free energy minimum, a significant energy barrier (~several kBT per nanometer of the nanorod) must be overcome, which helps explain the large mechanical modulus of the PBDT ion gel reported experimentally. / Ph. D. / Polymer electrolytes are an indispensable component in numerous electrochemical devices. However, despite decades of research and development, few existing polymer electrolytes can offer the electrochemical, transport, mechanical, and thermal properties demanded by practical devices and new polymer electrolytes are continuously being developed to address this issue. In this dissertation, the molecular structure and dynamics of three emerging novel polymer electrolytes, i.e., polymerized ionic liquids (polyILs), nanoscale ionic materials (NIMs), and polymeric ion gels, are investigated to understand how their transport and mechanical properties are affected by their molecular design. The study of polyILs focused on the interfacial behavior of a prototypical polyILs supported on neutral and charged quartz substrates. It was shown that the structure and diffusion mechanism of the interfacial polyILs are sensitive to the surface charges of the substrate and can deviate strongly from that in bulk polyILs. The study of NIMs focused on how the transport properties of the dynamically grafted polymers are affected by electrolyte ion pairs. It was discovered that the contaminated ions can affect the conformation the polymeric canopies and the exchange between the “free” and “grafted” polymers. The study of polymeric ion gels focused on the molecular and mesoscopic structure of the ionic liquids in the gel and the mechanisms of ion transport in these gels. It was discovered that the ions exhibit distinct structure at the intermolecular and the interrod scales, suggesting the formation of extensive electrostatic networks in the gel. The dynamics of ions captured in simulations is qualitatively consistent with experimental observations.

No / Phosphonium tosylates have been investigated as solvents for the Diels¿Alder reactions of isoprene with methyl acrylate, but-3-en-2-one and acrylonitrile. The reactions with oxygen-containing dienophiles showed high regioselectivity. Graphic

Líquidos iônicos (LI) e Poli(líquidos íonicos) (PLI) apresentam propriedades moduláveis extremamente interessantes, devido a possibilidade de infinitas combinações entre cátions e ânions, além da possibilidade de funcionalização tanto do cátion quanto do ânion para a inserção de propriedades de interesse, transformando esses LI e PLI em materiais de tarefa específica (task-LI e task-PLI). Nesta tese de doutorado, um PLI sólido, eletrocrômico e inédito foi sintetizado a partir de um LI funcionalizável e polimerizável (brometo de 1-cloropropil-3-vinilimidazólio) e o viologênio 4,4-bipiridina. Essa reação resultou em um monômero que teve sua estrutura intensamente elucidada e, em seguida, foi polimerizado, formando um polieletrólito sólido eletrocrômico estável mecanicamente e termicamente (309 °C). Os estudos espectroeletroquímicos a partir de um filme fino depositado sobre ITO revelaram um processo redox reversível com redução e oxidação nos potenciais de -0.45 e -0,3 V, respectivamente. O processo redox foi acompanhado por variação de coloração de transparente (estado totalmente oxidado) para roxo (estado reduzido/cátion radical) com contraste ótico de 19 % (525 nm), switching time de 20 s e eficiência da coloração (CE) de 60 cm2 C-1. A estabilidade eletroquímica do filme foi estudada via cronoamperometria e o material permaneceu eletroativo e eletrocrômico por 4 horas e 400 ciclos sem perdas consideráveis de eletroatividade. Além disso, mesmo após 16 h e 1600 ciclos o material apresentou eletroatividade com um decréscimo pequeno de corrente e variação de transmitância. Adicionalmente, o monitoramento do material com uma microbalança a cristal de quartzo com dissipação (QCM-D) indicaram que a compensação de carga do polímero é acompanhada por uma considerável variação de viscoelasticidade do filme e a principal espécie responsável pela compensação é o ânion, sendo o ânion volumoso [Tf2N] incapaz de compensar a carga do sistema impedindo o processo redox de ocorrer. Ainda com relação a capacidade de funcionalização dos LI, um LI inédito foi preparado a partir de um segundo LI funcionalizável (brometo de 1-cloropropil-1-metilpirrolidíneo) que foi elucidado por diversas técnicas incluindo ressonância magnética nuclear em duas dimensões de 1H, 13C e 15N (RMN 2D: COSY, NOESY, HSQC e HMBC) e RMN 15N. Dessa forma, um LI funcionalizado com aza-éter de coroa (LIcoroa) foi preparado a partir da reação do LI funcionalizável e o aza-18-coroa-6 e, novamente, a estrutura foi elucidada, incluindo RMN 2D. O LIcoroa apresentou boa estabilidade térmica (371 °C) e eletroquímica (janela de 4 V). A densidade do LI foi obtida no valor de 1,5 g cm-3 (25 °C). No entanto, a viscosidade do LI foi elevada afetando diretamente sua condutividade elétrica quando comparado com o LI bis(trifluorosulfonil)imida de 1-bultil-1-metilpirrolidíneo já amplamente estudado na literatura. Para aplicações, este LI coroa está sendo estudado para atuar como eletrólito em baterias de íon lítio devido a sua possível capacidade de complexar com este íon e diminuir a interação do Li+ com os oxigênios da espécie aniônica [Tf2N]. / Ionic Liquids (ILs) and poly(Ionic Liquids) (PoILs) have fully tunable properties due to their different ion combinations as well as cation or anion functionalization, which results in smart materials with endless possibilities. In this study, a solid electrochromic PoIL was synthesized using a novel functionalizable and polymerizable IL (1-propyl-3-vinylimidazolium chloride bromide) and a viologen (4,4\'-bipyridine) that reacted to form a monomer. Its subsequent polymerization resulted in a mechanically stable, highly ionically and electronically conductive electrochromic polyelectrolyte with a thermal decomposition temperature higher than 309°C and a glass transition temperature of 13°C. Spectroelectrochemical studies of the polymer deposited as a thin film over a transparent conductive substrate demonstrated a reversible redox process with reduction and oxidation potentials of -0.45 and -0.3V, respectively, which was accompanied by a reversible color change from colorless (oxidized state) to purple (reduced state) with an optical contrast of 19% at 525nm, a switching time of nearly 20s and a coloration efficiency of 60 cm2 C-1. Additionally, the film was repetitively switched from colorless to purple and began to lose electroactivity after approximately 4h and 400cycles. However, electroactivity was still observed after 16h or 1600cycles. Moreover, quartz crystal microbalance with dissipation monitoring indicated that the polymer charge compensation process was accompanied by a huge viscoelastic change in the film, as demonstrated by the spread of the harmonics and important changes in dissipation. Moreover, the anion is the most important specie in the charge compensation process, the large anion [Tf2N] is unable to compensate the charge, preventing the redox process from occurring. Also regarding the functionalization capacity of LI, a novel LI was prepared from a second functionalizable LI (1-chloropropyl-1-methylpyrrolidinium bromide) which was intensively elucidated by several techniques including two-dimensional nuclear magnetic resonance 1H, 13C and 15N (2D NMR: COSY, NOESY, HSQC and HMBC). Thus, a functionalized LI with aza-crown ether (LIcrown) was prepared from the reaction of the functionalizable LI and aza-18-crown-6 and, again, the structure was elucidated, including 2D NMR. LIcrown presented good thermal stability (371 ° C) and electrochemistry (4 V window). The density of the IL was 1,5 g cm-3. However, the viscosity of the LI was elevated by directly affecting its electrical conductivity when compared to the 1-butyl-1-methylpyrrolidinium bis(trifluorosulfonyl)imide already widely studied in the literature. For applications, this LIcrown is being studied to act as an electrolyte in lithium ion batteries because of its possible ability to complex with this ion and to decrease the interaction of Li+ with the oxygen of the anionic species [Tf2N].

The objective of this research is to explore the use of ionic liquds in crystal engineering and drug delivery. Ionic liquids have a wide range of applications in pharmaceutical field due to their unique physicochemical propertie ssuch as chemical, thermal stability, low melting point, nonvolatility, nonflamability, low toxicity and recyclability which offer unique and interesting potential for pharmaceuitcal applications. Currently, many research groups are working on the development of ionic liquids to use in this field but there is need to develop systematic understanding about new techniques for synthesis and applications of ionic liquids to obtain new crystal form and potential of drug ionic salts. The synthesis of fifteen phosphonium ionic liquids under microwave irradiation and their physicochemical properties was investigated. The reaction time was significantly reduced compared to conventional methods, and higher yields were reported. The crystallisation of pharmaceutical drugs such as sulfathiazole, chlorpropamide, phenobarbital and nifedipine were investigated using imidazolium ionic liquids. The supramolecular complex of sulfathiazole and phenobarbital with imidazolium ionic liquids and polymorphic change in chlorpropamide was achieved. The ionic liquids provides unique environment for the crystallisation. The imidazolium salts of ibuprofen and diclofenac were synthesised and evaluated for physicochemical properties and their pharmaceutical performances especially transdermal absorption. The investigation of physicochemcal properties and pharmaceutical performance of imidazolium drug salts indicated opportunity to optimise lipophilicity and other physicochemical properties such as molecular size, osmolality, viscosity to achieve desired skin deposition and permeation. This study will provide a new approach to design of new drug salts develop using the interdisciplinary knowledge of chemical synthesis and drug delivery.

Ionic liquids are salts that are in liquid form at room temperature. These compounds have been suggested to be environmentally friendly and are proposed to be replacements for commercially available solvents used in laboratory operations today. There is an increasing interest in these compounds, but toxicological data of ionic liquids are still scarce. In this project five imidazolium based ionic liquids, 1-etyl-3-methylimidazolium, 1-butyl-3-methylimidazolium, 1-hexyl-3-methylimidazolium, 1-octyl-3-methylimidazolium and 1-decyl-3-methylimidazolium were evaluated based on responses on aryl hydrocarbon receptor (DR-Ecoscreen), Nrf2 activity (MCF732cARE), androgen receptor (AR-Ecoscreen) and estrogen receptor (VM7Luc4ER). This was done with an effect based in vitro approach using luciferase bioassays. The results show that imidazolium based ionic liquids have the ability to induce androgen and estrogen receptor activity. It is also shown that imidazolium based ionic liquids can act as antagonists on the androgen receptor. Imidazolium based ionic liquids does not seem cause oxidative stress and is shown to not interact with the aryl hydrocarbon receptor. The ability of 1-octyl-3-methylimidazolium and 1-decyl-3-methylimidazolium to pass the gastrointestinal tract was also tested in a modified transwell caco-2 permeability test, which resembled the human GI-tract. It was shown to be difficult to evaluate if 1-octyl-3-methylimidazolium and 1-decyl-3-methylimidazolium have the ability to pass through the GI-tract and antagonize on the androgen receptor. These results are important from both an environmental as well as human health point of view if imidazolium based ionic liquids are to be accidentally or intentionally release into the environment.

No description available.

We report the use of imidazolium based tunable aryl alkyl ionic liquids (TAAILs) as solvents in the Mizoroki–Heck reaction. Different commercially available palladium sources, inorganic bases, TAAILs and reaction conditions were tested for the synthesis of trans-stilbene using bromobenzene and styrene. A variety of different stilbene derivatives were synthesized with exclusive formation of the (E)-isomers and isolated yields up to 97%. We were able to optimize the reaction conditions using only 0.25 mol% of Pd(OAc)2 as the catalyst and a reaction time of 4 hours. No additional ligands or additives are used in the reaction. The catalytic system using TAAILs achieved higher yields than commercially available imidazolium and phosphonium ionic liquids, demonstrating the potential of tailored ionic liquids as a reaction medium for the Mizoroki– Heck reaction.

Este trabalho tem como objetivo a síntese e a determinação de propriedades micelares de líquidos iônicos tensoativos (LITs) catiônicos. Dentre as características importantes desses compostos destacamos: alta deslocalização da carga e caráter ácido no hidrogênio H2 do anel heterocíclico e a grande flexibilidade estrutural, estas são relevantes para as propriedades de soluções desses tensoativos, e, consequentemente, para suas aplicações. A influência da variação estrutural nas suas propriedades é importante para modular as propriedades micelares e, por consequência suas aplicações. A síntese de LITs foi realizada por aquecimento convencional e irradiação por micro-ondas, o último método foi o mais eficiente. Inicialmente, estudamos a influência do comprimento da cadeia carbônica (fator importante para a energia de formação de micelas), de cloretos de 1-alquil-3-metilimidazólio, tendo a cadeia n-alquílica 10 a 16 átomos de carbonos. Em seguida, comparamos as propriedades dos LITs acima mencionados com as de tensoativos convencionais, cloretos de 1-alquilpiridínio e cloretos 1-alcanoil-amidoetil benzildimetilamônio. Por fim, estudamos a influência do volume da cabeça-polar, utilizando cloretos de 1-alquil-3-hexadecilimidazólio, tendo a cadeia alquílica secundária 1 a 5 átomos de carbono. As propriedades micelares foram investigadas por tensão superficial, condutividade, calorimetria, espalhamento de luz e ressonância magnética nuclear. Os resultados mostraram que ligações de hidrogênio (devido ao H2 ácido do anel imidazólio) e as interações hidrofóbicas são relevantes para a formação de micelas e que o aumento do volume da cabeça-polar favorece a micelização e a formação de agregados pré-micelares / The objective of this work is the synthesis and determination of the micelar properties of cationic surface-active ionic liquids (SAILs). Among the important characteristics of these compounds are: high charge delocalization and acid character of hydrogen H2 of the heterocyclic ring and large structural flexibility, the latter is relevant to solution properties of these surfactants, hence to their applications. Synthesis of SAILs was carried out by conventional heating or by microwave irradiation, the later method was more efficient. Initially, we studied the influence of the chain length of the alkyl group (an important factor for the energy of micelle formation) of 1-alkyl-3-methylimidazolium chlorides, n-alkyl group having 10 to 16 carbon atoms. Then, we compared the properties of the above mentioned SAILs with conventional surfactants, 1-alkylpyridinium chlorides and 1-alkanoyl-amidoethyl benzyldimethylammonium chlorides. Finally, we studied the influence of the head-group volume, by studying 1-alkyl-3-hexadecylimidazolium chlorides, with secondary n-alkyl group having 1 to 5 carbon atoms. The micelar properties were investigated by surface tension, conductivity, calorimetry, light scattering and nuclear magnetic resonance. Our results have shown that hydrogen bonding (due to the acidic H2 of the imidazolium ring) and hydrophobic interactions are relevant to micelle formation; increasing the head-group volume favors micellization and the formation of pre-micellar aggregates

Este trabalho tem como objetivo a síntese e a determinação de propriedades micelares de líquidos iônicos tensoativos (LITs) catiônicos. Dentre as características importantes desses compostos destacamos: alta deslocalização da carga e caráter ácido no hidrogênio H2 do anel heterocíclico e a grande flexibilidade estrutural, estas são relevantes para as propriedades de soluções desses tensoativos, e, consequentemente, para suas aplicações. A influência da variação estrutural nas suas propriedades é importante para modular as propriedades micelares e, por consequência suas aplicações. A síntese de LITs foi realizada por aquecimento convencional e irradiação por micro-ondas, o último método foi o mais eficiente. Inicialmente, estudamos a influência do comprimento da cadeia carbônica (fator importante para a energia de formação de micelas), de cloretos de 1-alquil-3-metilimidazólio, tendo a cadeia n-alquílica 10 a 16 átomos de carbonos. Em seguida, comparamos as propriedades dos LITs acima mencionados com as de tensoativos convencionais, cloretos de 1-alquilpiridínio e cloretos 1-alcanoil-amidoetil benzildimetilamônio. Por fim, estudamos a influência do volume da cabeça-polar, utilizando cloretos de 1-alquil-3-hexadecilimidazólio, tendo a cadeia alquílica secundária 1 a 5 átomos de carbono. As propriedades micelares foram investigadas por tensão superficial, condutividade, calorimetria, espalhamento de luz e ressonância magnética nuclear. Os resultados mostraram que ligações de hidrogênio (devido ao H2 ácido do anel imidazólio) e as interações hidrofóbicas são relevantes para a formação de micelas e que o aumento do volume da cabeça-polar favorece a micelização e a formação de agregados pré-micelares / The objective of this work is the synthesis and determination of the micelar properties of cationic surface-active ionic liquids (SAILs). Among the important characteristics of these compounds are: high charge delocalization and acid character of hydrogen H2 of the heterocyclic ring and large structural flexibility, the latter is relevant to solution properties of these surfactants, hence to their applications. Synthesis of SAILs was carried out by conventional heating or by microwave irradiation, the later method was more efficient. Initially, we studied the influence of the chain length of the alkyl group (an important factor for the energy of micelle formation) of 1-alkyl-3-methylimidazolium chlorides, n-alkyl group having 10 to 16 carbon atoms. Then, we compared the properties of the above mentioned SAILs with conventional surfactants, 1-alkylpyridinium chlorides and 1-alkanoyl-amidoethyl benzyldimethylammonium chlorides. Finally, we studied the influence of the head-group volume, by studying 1-alkyl-3-hexadecylimidazolium chlorides, with secondary n-alkyl group having 1 to 5 carbon atoms. The micelar properties were investigated by surface tension, conductivity, calorimetry, light scattering and nuclear magnetic resonance. Our results have shown that hydrogen bonding (due to the acidic H2 of the imidazolium ring) and hydrophobic interactions are relevant to micelle formation; increasing the head-group volume favors micellization and the formation of pre-micellar aggregates

The objective of this research is to explore the use of ionic liquds in crystal engineering and drug delivery. Ionic liquids have a wide range of applications in pharmaceutical field due to their unique physicochemical propertie ssuch as chemical, thermal stability, low melting point, nonvolatility, nonflamability, low toxicity and recyclability which offer unique and interesting potential for pharmaceuitcal applications. Currently, many research groups are working on the development of ionic liquids to use in this field but there is need to develop systematic understanding about new techniques for synthesis and applications of ionic liquids to obtain new crystal form and potential of drug ionic salts. The synthesis of fifteen phosphonium ionic liquids under microwave irradiation and their physicochemical properties was investigated. The reaction time was significantly reduced compared to conventional methods, and higher yields were reported. The crystallisation of pharmaceutical drugs such as sulfathiazole, chlorpropamide, phenobarbital and nifedipine were investigated using imidazolium ionic liquids. The supramolecular complex of sulfathiazole and phenobarbital with imidazolium ionic liquids and polymorphic change in chlorpropamide was achieved. The ionic liquids provides unique environment for the crystallisation. The imidazolium salts of ibuprofen and diclofenac were synthesised and evaluated for physicochemical properties and their pharmaceutical performances especially transdermal absorption. The investigation of physicochemcal properties and pharmaceutical performance of imidazolium drug salts indicated opportunity to optimise lipophilicity and other physicochemical properties such as molecular size, osmolality, viscosity to achieve desired skin deposition and permeation. This study will provide a new approach to design of new drug salts develop using the interdisciplinary knowledge of chemical synthesis and drug delivery. / Social Justice Department, Government of Maharashtra, India.