Dissertations / Theses on the topic 'Chiral ionic liquids'

Chiral ionic liquids have been present in the literature for more than a decade. The development of original chiral systems of ions is currently far more difficult than ever before. The path of innovation in this topic, however, should not be focussed exclusively on the introduction of chirality into the ionic liquid structure, but should go beyond, towards further functionalisation of these species. The combination of chirality and a functional moiety has been the starting point for the present work. Here, a focus was on creation of chiral ionic liquids possessing distinct functional groups: a strong hydrogen-bonding thiourea group was selected. Consequently, a series of novel chiral thiouronium salts were synthesised. The chirality was sourced in cheap, but structurally robust, chiral amines: (S)-1- phenylethylamine and (+)-dehydroabietylamine. Because the thiourea moiety can be functionalised at five different sites, a wide range of thiouronium and thiourea-functionalised ionic liquids could be prepared and analysed, and the influence coming from their structural diversity explored. The crucial point for the project was a confirmation of rotameric behaviour in these new thiouronium systems. Here, the hindered rotation has been examined by NMR spectroscopy, and compared with literature findings. The key message concludes that, in the thiouronium system, the C-S rotation predominates when placed in a highly polar solvent; then the syn syn conformation dominates. When, on the other hand, the constraints of the surroundings are eliminated, the syn-anti form is energetically preferable. Here, the rotamerism of the thiouronium cation in a neat liquid form was examined for the first time. Finally, these novel chiral compounds have found applications based on molecular recognition by the thiourea moiety. The discrimination of chiral oxoanions by these salts using NMR spectroscopy has been successful. A strong, double hydrogen-bonded connection between the chiral thiouronium moiety and the oxoanion proved to be a key point, generating results a competitive with the literature results. Following this approach, the separation capabilities of thiouronium systems were also explored, given that they can be effective agents for oxoanion extractions. This work demonstrated that a careful design of functional molecules is scientifically significant, and can have a great impact on their applications.

The backbone of this work is to make a chiral ionic liquid with enantioselective properties. It is envisaged that the ionic liquid will be a component part of a gel matrix, or membrane, which holds a racemic drug in solution, and shows preferential affinity to one enantiomer. This would allow favoured diffusion of the unattached enantiomer, and such a system would be ideal as the reservoir in a drug delivery system. To test this idea, chiral amino acid ionic liquids were used. The thesis introduces ionic liquids by definition, classification, properties and industrial applications, and also the anti-inflammatory drug ibuprofen as the model test compound. The main application, discussed in Chapter 2, was the separation of ibuprofen enantiomers using chiral amino acid ionic liquids as the chiral selector with liquid-liquid extractions. Ionic liquid preparation is included in Chapter 3, as is an overview of HPLC analysis. Chiral interactions may depend on many factors, and these are explained in Chapter 4. Interaction experiments were performed, and techniques complementary to HPLC also explored. Chapter 5 highlights the subtle nature of enantiomeric separations. Here, an increase in enantiomeric excess percentage by physical processes was demonstrated using ionic liquid test strips. They were developed to help determine enantiomeric excess of ibuprofen as it passed through a series of ionic liquid impregnated sections on paper or silica. In Chapter 6, the analytical and preparative technique of countercurrent chromatography is discussed. It concludes with an application that used a thiouronium based ionic liquid to resolve racemic mandelic acid. Overall, the aim was not to develop and optimise a specific application, but to demonstrate proof-of-principle for using chiral ionic liquids to achieve enantiomeric separation. Two new methodologies were unambiguously demonstrated: the use of paper strips and countercurrent chromatography, and both appear to be worthy of future development.

This thesis involves the synthesis of two main classes of triaminocyclopropenium (tac) Ionic Liquids (ILs) (i) Amino Acid Ionic Liquids (AAILs) and (ii) reduced-symmetry cations. [C₃(NEt₂)₂(NRR’)]X (X = TFSA and MeSO₄) were prepared, whereby NHR is derived from amino acids. Optically pure AAILs, [E₄AminoAcid]X (X = TFSA and MeSO₄) were obtained as a mixture of the IL and its zwitterion. The ratios of these mixtures were determined by pH titration and microanalysis. The AAILs specific rotations and pKa values were determined. AAILs can be used for chiral discrimination and form diasterreomeric salts with the entioenriched sodium salt of Mosher’s acid. The AAILs were also successfully used as a solvent and/or catalyst in an aldol reaction and a Diels-Alder reaction. The low-molecular weight series, [C₃(NMe₂)₂(NRR’)]X and [C₃(NMe₂)₂(NR’2)]X was synthesized and characterized: protic ILs NRR’, where R = ethyl, propyl, allyl, butyl, - CH2CH2OCH₃ and pentyl, R’ = H and X = TFSA: and aprotic ILs NRR’, where R = Me, R’ = ethyl, allyl, propyl, butyl, -CH2CH2OCH₃ and hexyl and X = TFSA and DCA. ILs with C2v symmetry [C₃(NEt₂)₂(NH2)]X (X = TFSA and MeSO₄), [C₃(NEt₂)₂(NBu2)]I, [C₃(NEt₂)₂(NHex₂)]I and [C₃(NEt₂)₂(NHex₂)]OTf were also synthesized and characterized. The C₃h cations, [C₃(NMeR)₃]X (R = ethyl, allyl, -CH2CH2OCH₃ and phenyl, X = TFSA and DCA) were successfully prepared as well. The D₃h cation salts [C₃(NEt₂)₃]X (X = MeC6H4SO₃, OTf, I and F5C6O) and [C₃(NBu2)₃]X (X = B(CN)4 and FAP) were also prepared. The tac-based ILs [C₃(NEt₂)₃]+ and [C₃(NBu2)₃]+ were also complexed with metal halides - - 2- 2- forming salts with FeCl₄ , SnCl₃ , CuCl₄ and ZnCl₄ . Reaction of pentachlorocyclopropane (C₃Cl5H) with BuNH2 gave the open ring allylium product [H2C₃(NBuH)4]2+. This was characterized as Cl- and TFSA- salt. During the synthesis of [C₃(NMe₂)₃]Cl, the open ring cation [HC₃(NMe₂)4]+ was also isolated and was characterized as the TFSA- salt. XX Abstract The TGA, DSC, density, viscosity, conductivity, and molar conductivity properties for the ILs were measured where possible. The viscosity and conductivity data was fitted for the Arrhenius and Vogel-Fulcher Tamman equations. The entire tac-based ILs lie below the KCl ideal line in Walden plot. A fragility plot was obtained by fitting the viscosity data and all the tac-based ILs were fragile. The crystal structures of [C₃(NPhH)₃]TFSA, [C₃(NEt₂)₃]FeCl₄ and [HC₃(NMe₂)4]Cl.2CH₃Cl were determined.

The main objective of this thesis is to identify a generic approach for the application of ionic liquids to bioconversions. Key factors for the operation of bioconversions in ionic liquids have been identified and product recovery options investigated. Two bioconversions were examined. The first was the hydrolytic resolution of racemic 2,3,4,5-tetrahydro-4-methyl-3-oxo-lH-l ,4-benzodiazepine-2-acetic acid methyl ester (SB-235349) to (2S)-2,3,4,5-tetrahydro-4-methyl-3-oxo-lH-l,4- benzodiazepine-2-acetic acid (SB-240101) by immobilised Candida antarctica lipase B, CALB (Novozyme 435), performed industrially in t-butanol. Initial studies showed this reaction occurred in several ionic liquids with different physico-chemical properties. Simply replacing the organic solvent with an ionic liquid under otherwise identical conditions reduced the rate of conversion and overall yield. The key factors influencing the rate and yield of this bioconversion in ionic liquids were the type of ionic liquid and the substrate solubility, the reaction temperature and the water content. The final optimised reaction in ionic liquids shows an eighteen-fold enhancement in product formation compared to the optimised t-butanol system. In order for ionic liquids to be applied commercially there are still many issues which still need to be resolved these include: the extraction of substrates and products from the ionic liquid media for down stream processing, and the recycle of the media for subsequent reactions. The next step having optimised the CALB bioconversion of SB- 235349 in ionic liquid media was to extract the SB-240101 product and the un-reacted SB-235349 substrate in order to recycle the ionic liquid. The SB-240101 produced by the reaction was removed by liquid-liquid extraction with 50mM bicarbonate buffer (pH 10); overall 93% of the SB-240101 produced was removed from the ionic liquid into the aqueous buffer phase. The un-reacted 2,3,4,5-tetrahydro-4-methyl-3-oxo-lH- 1,4-benzodiazepine-2-acetic acid methyl, ester (SB-240098) was removed by liquid- liquid extraction with isopropyl alcohol, and 91% was removed from the ionic liquid. The ionic liquid was then regenerated with sodium hydroxide for recycle. The results from the bioconversion with fresh and recycled ionic liquid were almost identical, in both cases around l.8g.L-1 of product was produced in 6 hours. The two-phase extractions were subsequently studied in the Lewis cell, and the mass transfer rate (K0) examined for the extraction of both the substrate and the product from the ionic liquid. Values of K0 determined in the Lewis cell over the Reynolds number range for which a flat, non-perturbed, interface could be maintained were in the range 1.0 - 3.5 X 10-6 m.s-1 for both product and substrate extraction. In both extraction experiments there was a linear increase in K0 with Reynolds number. The second bioconversion the thymidine phosphorylase catalysed synthesis of thymidine from thymine, which is traditionally performed in aqueous media, was then examined in ionic liquids. Initial investigations of this conversion step showed that replacing the aqueous media with an ionic liquid like [BMIM][PF6] under otherwise identical reaction conditions reduced the overall yield, which is attributed to the low solubility of the reagents in this ionic liquid. As the first constraint of the aqueous system was the solubility of the substrates and products; work then focused on those ionic liquids that showed a high solubility for thymine and especially thymidine. A study of the conversion in these high solubility ionic liquids showed conversion to the same degree as that demonstrated in aqueous media. An examination of product recovery from [EMIM][tosylate] following the thymidine transformation showed that the most likely method of product recovery was adsorption to an anion exchange resin 1-X8. In summary the results presented in this thesis show that ionic liquids offer significant advantages as alternative reaction media in industrial bioconversions. These are related to the excellent solvation properties of ionic liquids, and the tunable physicochemical properties of ionic liquids such as miscibility (or immiscibility) with water by changes in the anion or cation. Overall this thesis has identified generic procedures for the design of bioconversions and product recovery options in ionic liquids that have been exemplified using two different bioconversion systems.

The use of ionic liquids (ILs) as both reagents and solvents is widely recognised. ILs offer a number of advantages compared to regular molecular solvents. These advantages include: chemical and thermal stability, no measurable vapour pressure, no or lower toxicity, non-flammability, catalytic ability, high polarity and they can be recycled. There are a number of research groups investigating the various applications of this reaction medium and most studies have focused on solvents derived from the imidazolium cation. The use of the imidazolium-based ILs in the Diels-Alder reaction has been studied in detail and higher yields compared to conventional methods have been reported. The IL affects the rate and interesting selectivities have been observed. However, not much attention has been paid to the scope and limitations of phosphonium ILs (PILs). Therefore the focus of this thesis is the synthesis and application of novel chiral PILs as environmentally benign, task-specific solvents for the Diels-Alder reaction. In addition, this research seeks alternative ways to eliminate the use of toxic heavy metal catalysts and to exploit methodologies which reduce the energy consumption of the Diels-Alder reaction. A series of CILs were synthesised from the chiral pool and they were characterised by thermogravimetric analysis, differential scanning calorimetry and spectroscopy. They were then investigated as solvents and catalysts in the Diels-Alder reactions of a series of dienes (cyclopentadiene, isoprene, 2,3-dimethylbuta-1,3-diene, furan, pyrrole, N-methyl pyrrole) and dienophiles (methyl acrylate, methyl vinyl ketone, acrylonitrile, dimethyl maleate, acrolein, dimethylacetylene dicarboxylate, maleic anhydride and maleimide). Investigation of the effect of PILs in the presence of three heterogeneous catalysts Al2O3, SiO2 and K-10 montmorillonite were studied. Ultrasound and microwave-assisted Diels-Alder reactions in the PILs, in the absence and presence of the catalysts, were also studied. The reactions of these prototypical substrates illustrated that the solvents are indeed task-specific.

Doutoramento em Química
Nas últimas décadas, os líquidos iónicos (ILs) têm sido alvo de elevado interesse quer por parte da academia como a nível industrial. Isto deve-se em grande parte às suas propriedades únicas, assim como à possibilidade de, através de uma apropriada combinação dos seus iões, ser possível ajustar as suas propriedades para uma dada aplicação. Assim, os ILs têm vindo a ser considerados uma abordagem inovador para a “Química verde” e para a sustentabilidade. Contudo, a sua solubilidade em água faz com que estes possam facilmente chegar ao ecossistema aquático, podendo representar um perigo para este. O principal objetivo deste trabalho é estudar novos ILs, mais sustentáveis, assim como algumas das suas potenciais aplicações. Assim, foram investigados ILs como sendo antioxidantes, seletores quirais, hidrótopos, surfactantes, compostos magnéticos, assim como novos compostos hidrofóbicos. Para cada classe de ILs, foi estudada a sua síntese, caracterização físico-química e perfil de ecotoxicidade. Os novos ILs antioxidantes preparados neste trabalho foram avaliados quanto à sua solubilidade em água, estabilidade térmica, citotoxicidade e ecotoxicidade. Foram também estudados vários ILs quirais, quer baseados em aniões quirais (derivados de vários aminoácidos e do ácido tartárico), quer em catiões quirais (derivados da quinina, L-prolina e L-valina), no que respeita à sua estabilidade térmica, rotação ótica e ecotoxicidade. Além disso, foi avaliado o impacto de diferentes estruturas químicas dos ILs, assim como da sua concentração, na solubilidade de fármacos com reduzida solubilidade em água, a fim de analisar o seu comportamento enquanto hidrótopos cataniónicos. Entre as estruturas mais hidrofóbicas referidas neste trabalho estão vários ILs com natureza surfactante e um IL hidrofóbico baseado no anião per-fluoro-tertbutóxido. Relativamente aos ILs com carácter surfactante, foram preparados ILs pertencentes à família dos imidazólios, amónios quaternários e fosfónios, sendo posteriormente avaliados quanto à sua natureza de agregação, propriedades térmicas, ecotoxicidade, e à sua capacidade em promover disrupção celular. Por sua vez, o IL baseado no anião per-fluoro-tert-butóxido foi estudado relativamente às suas propriedades físicas, tais como a sua densidade, viscosidade e tensão superficial, assim como à sua toxicidade. Por fim, 24 ILs magnéticos foram preparados conjugando o catião colínio com diferentes aniões magnéticos ([FeCl4]-, [MnCl4]2-, [CoCl4]2- and [GdCl6]3-), sendo seguidamente avaliados quanto à sua ecotoxicidade. Visando o desenho racional de novos ILs, foi desenvolvido um modelo preditivo QSAR, onde foram utilizandos os dados de ecotoxicidade medidos neste trabalho. As previsões deste modelo relativamente à não toxicidade de um certo número de novos ILs foram testadas com êxito através da síntese destes compostos e posterior avaliação da sua ecotoxicidade utilizando o bioensaio Microtox.
Due to their unique properties, ionic liquids (ILs) have attracted an increased scientific and industrial attention in the last decades. The possibility of tailoring their properties for a specific task by the adequate combination of their ions, makes these ionic compounds good candidates for a wide range of different applications. Actually, ILs have been described as an innovative approach to the “Green Chemistry” and sustainability principles. However, their solubility in water allows their easy access to the aquatic compartment, which makes them potentially hazardous compounds to aquatic organisms. The main goal of this work is to study new, more environmental friendly, IL structures and their main applications. ILs as antioxidants, chiral selectors, hydrotropes, surface-active compounds, with magnetic properties, as well as, new hydrophobic compounds are investigated. The synthesis, physico-chemical characterization and ecotoxicity profile were studied for the various classes of task specific ILs evaluated. New cholinium-based ILs with antioxidant nature were studied regarding their solubility in water, thermal stability, cytotoxicity, and ecotoxicity. Moreover, a large range of chiral ILs (CILs) based on several chiral anions (derived from chiral amino acids and tartaric acid) and chiral cations (based on quinine, L-proline and L-valine), was investigated and their thermal stability, optical rotation and ecotoxicity evaluated. Furthermore, the impact of different ILs structures and concentrations on the solubility of poorly water-soluble drugs was studied, and their role as catanionic hydrotropes investigated. Among the most hydrophobic structures reported in this work are several surface-active ILs and a hydrophobic IL based on the per-fluoro-tert-butoxide anion. The tensioactive ILs, belonging to the imidazolium, quaternary ammonium and phospholium families were tested in terms of their aggregation behavior, thermal properties, ecotoxicity, and their capacity to promore cell disruption. On the other hand, the per-fluoro-tert-butoxide-based IL was evaluated regarding its physical properties, such as density, viscosity, and surface tension and toxicity. Finally, 24 magnetic ILs belonging to the cholinium family and using [FeCl4]-, [MnCl4]2-, [CoCl4]2- and [GdCl6]3- as anions were investigated and their ecotoxicity evaluated. Aiming at the rational design of ILs, a predictive QSAR model was developed with our help, and using ecotoxicity data measured in this work. The predictions of this model concerning the non-toxicity of a number of novel ILs were successfully tested by synthesizing these compounds and evaluating their toxicity using the Microtox bioassay.

This project divides into two halves: the synthesis, purification and characterisation of numerous ionic liquids including amino acid based chiral ionic liquids and polarity studies, which have been undertaken to further the understanding and quantification ofthe solvent-solute interactions by use of Kalmet-Taft measurements. In the early 1980s, the introduction of cleaner technologies to eliminate or significantly reduce hazardous waste generation became a major concern. In particular, a high priority to find alternatives to volatile organic compounds (VOC's), which were found to be very damaging solvents, was realised. Ionic liquids (IL's) remained a curiosity until recently, when the chemists discovered that it was possible to replace the VOC's with IL's and in some cases, the reactions were much improved. Since then, the field of IL's has exploded, which led to a vast increase in the number of publications and in the number of groups throughout the world who have started to work in the field. This project has reviewed some of the synthesis, purification and characterisation of chiral amino acid ILs and improved upon these procedures. The second halfofthe project involved investigating the overall solvating ability some of these purified IL's to obtain a better understanding ofhow these solvents may affect a reaction. This ability is not dependant on one particular physical measurement of the solvent, but is rather a sum ofall the specific and non-specific interactions that might occur between a solvent and solute. A large number of interactions are involved; these could include columbic, directional, inductive, dispersion, hydrogen-bonding, and electron pair donor/acceptor forces. The polarity ofthe IL's and mixtures of ILs with water or dichloromethane were investigated using UV dyes.

Mestrado em Biotecnologia - Industrial e Ambiental
Tipicamente, apenas um dos enantiómeros é responsável pelo efeito pretendido de um fármaco, sendo que o outro pode levar a respostas menos potentes ou até mesmo indesejadas. As entidades reguladoras praticam políticas restritas em relação à comercialização de fármacos como misturas racémicas. Assim, a indústria farmacêutica tem enfrentado desafios relacionados com o desenvolvimento de métodos para produção de fármacos oticamente puros. No entanto, e considerando a dificuldade acrescida na produção de enantiómeros puros por síntese direta, a síntese de misturas racémicas seguida da sua purificação surge como uma alternativa mais barata, simples e flexível. Os sistemas aquosos bifásicos (SABs) e os sistemas de duas fases sólida-líquida (SDFSL) são técnicas alternativas mais biocompatíveis que têm sido utilizados como técnicas de separação enantiosseletiva de fármacos e/ou aminoácidos com enantiosseletividades bastante promissoras. Para além disso, apresentam benefícios de custo, rapidez, simplicidade e versatilidade de operação e possibilidade de aumento de escala. Este trabalho foca-se no desenvolvimento de SABs e SDFSL constituídos por seletores quirais que possam atuar simultaneamente como solvente. Numa primeira abordagem o objetivo foi desenvolver novos SABs quirais, mais biocompatíveis, simples e eficientes. Para tal, SABs constituídos por açúcares, aminoácidos e líquidos iónicos quirais foram aplicados na resolução enantiomérica de ácido mandélico racémico. O sistema mais promissor, composto por [C1Qui][C1SO4] + K3PO4, obteve um excesso enantiomérico de -33.4%. Numa segunda abordagem, foi possível criar uma alternativa mais simples e mais eficiente recorrendo a SDFSL. Com estes sistemas, foi obtido o valor mais elevado de excesso enantiomérico deste trabalho, de 49.0%, através da precipitação enantiosseletiva do R-ácido mandélico por interação com [N4444][D-Phe].
Conventionally, only one of the enantiomers is responsible for the intended effect of a drug, whilst the other may lead to a less potent or even undesired response. Regulation entities are very strict regarding the commercialization of racemic drugs. Thus, pharmaceutical industry has been facing challenges related to the creation of methods to produce optically active drugs. However, considering the increased difficulty in the production of pure enantiomers by direct synthesis, the synthesis of racemic mixtures followed by their purification appears as a cheaper, simpler and more flexible alternative. Aqueous biphasic systems (ABS) and solid-liquid biphasic system (SLBS) are more biocompatible alternatives that have been used to separate racemic drugs and amino acids with promising enantioselectivities. Furthermore, these are cost-effective, quick, simple and operationally flexible. This work intended to develop ABS and SLBS using chiral selectors that can simultaneously act as solvents. In a first attempt, chiral ABS of better biocompatibility, simplicity and efficiency were developed. For that purpose, ABS constituted by sugars, amino acids and chiral ionic liquids (CILs) were applied for chiral resolution of racemic mandelic acid (MA). The most promising ABS was a system composed of [C1Qui][C1SO4] + K3PO4 which yielded the maximum enantiomeric excess of -33.4%. In a second approach, it was possible to create a simpler and more efficient technique resorting to SLBS. The enantiomeric excess value of 49.0% was achieved, by the enantioselective precipitation of the R-MA caused by interactions with [N4444][D-Phe].

In this thesis, the results of synthesis of chiral ionic liquids (ILs) and an investigation of their application in chiral separation and catalysis are described. The study of the chiral lLs application was performed using liquid-liquid extraction, crystallization and asymmetric catalysis with analysis of substrate content and enantioselectivity by High Performance Liquid Chromatography (HPLC) . A series of chiral lLS with chiral cations or chiral anions were synthesized through alkylation or anion exchange with optical pure starting materials as the •chiral pool", Properties of chiral ILS made in house were studied using various techniques, The structures and configurations of the chiral ILs can be altered easily to meet the required physical properties, such as melting point and viscosity, Chiral! ILs made in house show chiral affinity with a range of racemic compounds, In the liquid-liquid extraction of menthol from chiral lL, good extraction is observed from the chiral lL layer into alkane !layer without visible leaching of the chiral lL into the alkane layer. In the mandelic acid resolution by • Dutch resolution", 22 different ILS were used as additive in the chiral selector, In general, ILS exhibit a equalize effect on both yield and ee of the final product. For the asymmetric catalysis study, both Mukaiyama-aldol reaction and Diels-Alder reaction were investigated with Cu(II)-PhBOX and Zn(II)-PhBOX as catalyst. In the Mukaiyama-aldol reaction, chiral ILS can be applied . as ligand and an increased ee is observed as compared with the reactions in the absence of the Il. In the Diels-Alder reaction, addition of the chiral Il 19 (Il of (1R,2S.5R)- menthol) with Zn(II)-PhBOX led to an increase in the endo ee from 5 % in DCM, 68 % in ether and 57 % in pure (C 2mim][NH 10 91 % under homogeneous reaction condition and 95 % in biphasic system with both high conversion and high endo selectivity. The endo selectivity of biphasic system with the chiral lL 1 g, [C2mim][NTf21 and ether is 99 %, which means nearly all product goes into endo form with 95 % ee.

In der vorliegenden Dissertation geht es um die Synthese und Charakterisierung chiraler, redoxaktiver (Raumtemperatur-)Ionischer Flüssigkeiten basierend auf Ferrocen und der natürlich vorkommenden Aminosäure S-Prolin. Diese Baueinheiten sind entweder über eine Ether- oder über eine Esterverbrückung verknüpft. Auch der Anionenaustausch vom I– - zum CF3SO3– - sowie (CF3SO2)2N– -Salz (kurz NTf2–) wird dargelegt und der Einfluss des Anions auf den Schmelzpunkt der Verbindungen untersucht und diskutiert. Die Redoxaktivität wird durch das im Ferrocen enthaltene Fe II eingebracht, das reversibel zu Fe III oxidiert werden kann. Aufgrund des Pyrrolidin-Rings sind die dargestellten Verbindungen stets chiral und bilden nach der Quaternisierung mit Halogenalkanen Diastereomere, soweit die Alkylkette größer als Methyl ist. Das Diastereomerenverhältnis wurde mittels 1H-NMR-Spektroskopie und in einem Fall anhand von Röntgenpulverdiffraktogrammen durch Rietveld-Verfeinerung analysiert. Die Verbindungen wurden thermisch anhand simultaner thermischer Analysenund Tieftemperaturversuchen untersucht, die belegen, dass die Synthese von insgesamt sechs neuen Raumtemperatur-Ionischen Flüssigkeiten gelang. Davon basiert eine Verbindung, (1S2S)- und (1R2S)-2-[(Ferrocenylcarbonyl)oxy]methylen-N-methyl-N-pentylpyrrolidin-1-iumiodid, auf I– und fünf Verbindungen enthalten NTf2– als Gegenion. Das Diastereomerengemisch der Verbindungen (1S2S)- und (1R2S)-N-Butyl-2-[(ferrocenylcarbonyl)oxy]methylen-N-methylpyrrolidin-1-ium NTf2– besitzt den größten Flüssigkeitsbereich von -25 bis +263 °C und auch die höchste Zersetzungstemperatur aller hier dargestellten Verbindungen. Insgesamt werden in dieser Arbeit elf Einkristallstrukturanalysen vorgestellt, wobei es sich um drei Verbindungen des Typs FcCH2N(CH3)2(CnH2n+1)I (Fc = Ferrocenyl, n = 1,2,3), Ferrocenmonocarbonsäurechlorid, zwei ether- sowie fünf esterverbrückte Verbindungen handelt. Mikrokristalline Proben wurden mittels Röntgenpulverdiffraktometrie charakterisiert. Ergänzende Analysen wurden mittels UV-Vis- und IR-Spektroskopie sowie Massenspektrometrie und Elementaranalyse durchgeführt. Ein wichtiger Aspekt bei Ferrocenverbindungen ist das Redoxpotential, welches mittels Cyclovoltammetrie bestimmt wurde. Hierbei liegt das Formalpotential des Fe II /Fe III -Redoxpaars der etherverbrückten Verbindungen bei +0,05 V und bei den esterverbrückten Verbindungen unabhängig vom Anion bei +0,28 V vs. Ferrocen/Ferrocenium in Acetonitril. Bei den iodidhaltigen Verbindungen zeigt das I– -Ion ebenfalls eine Redoxaktivität bei E(0,f,Fc) = -0,18 V und 0,22V. Die Diffusionskoeffizienten der esterverbrückten Triflat- und NTf2– -Verbindungen liegen in der Größenordnung von 7·10−6 cm2/s und die heterogenen Geschwindigkeitskonstanten bei 0,01 cm/s
The present dissertation deals with the synthesis and characterization of chiral, redoxactive room temperature ionic liquids (RTILs) based on ferrocene and the naturally occurring amino acid S-proline. These building blocks are coupled either via an ether- or an ester-bridge. The anion exchange from I– to CF3SO3– and (CF3SO2)2N– salts (abbreviated as NTf2–) is presented. The influence of the anion on the melting point of the compound is investigated and discussed. The redox activity is introduced into the molecule via the Fe II -containing ferrocenyl groups, which can be oxidized reversibly to Fe III . The synthesized compounds based on the pyrrolidine ring are chiral. After quaternization with alkyl halides, they form diastereomers in case of alkyl chains longer than methyl. The ratio of the different diastereomers was analyzed by 1H NMR spectroscopy and, in one case, by Rietveld refinement of the X-ray powder diffraction pattern. The thermal behavior of the compounds was studied by simultaneous thermal analysis and low temperature experiments. The results show the successful synthesis of six new RTILs. One of them is based on iodide ((1S2S)- and (1R2S)-2-[(ferrocenylcarbonyl)oxy]methylene-N-methyl- N-pentylpyrrolidine-1-ium iodide) and six RTILs contain NTf2– as counter ion. The diastereomeric mixture of compounds (1S2S)- and (1R2S)-N-butyl-2-[(ferrocenylcarbonyl)oxy]methylene-N-methylpyrrolidine-1-ium NTf2– exhibits the widest liquid range from -25 to +263 °C and the highest decomposition temperature of all compounds presented herein. Eleven single crystal structure analyses are presented. Three of them belong to compounds FcCH2N(CH3)2(CnH2n+1)I (with Fc = ferrocenyl and n = 1,2,3), then ferrocene monocarboxylic acid chloride, two of ether- as well as five ester-bridged compounds. Microcrystalline samples were characterized by X-ray powder diffractometry. Supplementary analyses by UV/Vis and IR spectroscopy as well as mass spectrometry and elemental analyses have been carried out. An important feature of ferrocene containing compounds is their redox potential which is determined with cyclic voltammetry. The formal potential of the Fe II /Fe III redox couple in the ether-bridged compounds is at +0.05 V and in the ester-bridged compounds independent from the type of anion at +0.28 V vs. ferro- cene/ferrocenium in acetonitrile. The I– anion shows as well redox activity with formal potentials at E(0,f,Fc) = -0.18 V and 0.22 V. The diffusion coefficients of the ester-bridged triflate and NTf2– compounds are in the order of 7·10−6 cm2/s, the heterogeneous rate constants in the order of 0.01 cm/s

Durant les darreres dècades, el disseny de processos en el marc de la química sostenible ha anat creixent de forma exponencial. La recerca constant de processos mes benignes amb el medi ambient ha implicat un gran esforç per obtenir millors rendiments mitjançant l'activació de llocs específics, i possant especial èmfasi amb el control de la quimio-, la regio- i la enantioselectivitat, punts crucials per a l'economia atómica. En aquest sentit, els dissolvents juguen un paper crític, i com podrà veure's al llarg d'aquesta memòria..
Aquesta Tesi s'enfoca en l'ús de mitjans de reacció alternatius i sostenibles, com són els líquids iònics (ILs), el diòxid de carboni supercrític (scCO2) i la barreja de ambdós dissolvents, amb l'objectiu de disminuir l'ús de dissolvents orgànics convencionals i la seva aplicació en els següents processos catalítics: hidrogenació asimètrica, reacció de Suzuki d'acoblament creuat C-C, reacció d'alquilació al·lílica asimètrica i la hidrogenació de arens.
In the last decades, the design of processes in the framework of the sustainable chemistry has been exponentially growing. The constant searching of cleaner processes has led to a lot of effort to obtain higher yields by activation of specific sites, and improving chemo-, regio- and enantio-selectivities, which are crucial from a point of view of an atom economy strategy. In this sense, solvents play a critical role.
This PhD thesis focuses on the use of alternative sustainable reaction media such as ionic liquids (ILs), supercritical carbon dioxide (scCO2) and mixtures of both solvents in different catalytic processes, with the aim of decreasing the use of conventional organic solvents applied in the following catalytic reactions: homogeneous and supported rhodium catalysed asymmetric hydrogenation, biphasic palladium catalysed Suzuki C-C cross-coupling, homogeneous palladium catalysed asymmetric allylic alkylation, and ruthenium and rhodium nanoparticles catalysed arene hydrogenation were tested.

Yes
A series of novel nopyl-derived chiral phosphonium ionic liquids have been successfully synthesised and characterised. Analysis of each novel ionic liquid was conducted in order to confirm structure, purity and thermal stability.
The full-text of this article will be released for public view at the end of the publisher embargo on 19 Jul 2021.

碩士
國立交通大學
光電科技學程
103
This thesis focuses on inveatigating the effect of chiral additives on the ionic behaviors of a cholesteric liquid crystal (CLC) by means of dielectric spectroscopy. In this study, two kinds of chiral additives—R5011 with right-hand chirality and S5011 with left-hand chirality were used and doped individually into the nematic LC host E44 to form right-hand and left-hand CLCs, respectively. In addition, chiral/LC mixtures with racemic molecular structure were also prepared by mixing right-hand and left-hand CLCs with identical chiral concentration in a weight ratio of 1:1. Based on measured dielectric results, the dielectric spectra of CLC cells in the low-frequency regime (f  ≤  1 kHz）characterized by space-charge polarization, are discussed to characterize the impurity-ion properties of CLC cells. By further fitting the dielectric results to deduce the dc conductivity, ion density and ion duffusivity, the ionic contribution of the chiral additives in CLCs is clarified. In cases of CLC cells with fixed chiral concentration, results from transmission and dielectric spectra suggest that the optical profiles and dielectric properties of a CLC do not be affected by the cell configuration (i.e., planar and 90° twisted alignments). On the other hand, For CLCs containing single type of chiral additives, experimental results indicate that the ionic effect of the CLCs doped with R5011 is higher than that of pure host LC E44 and it is enhanced with increasing dopant concentration of R5011. In contrast, the ionic properties of CLCs with S5011 is identical to that of pure E44 and it is nearly invariance to the S5011 concentration. Specifically, it is found that the ionic behavior of the chiral/LC mixtures with racemic structure depends on the content of R5011. For the CLC consisting of a nematic LC host doped with chiral additives, It can be concluded from aforementioned results that the strength of ionic effect is determined by the ionic properties of the host LC and chiral additives rather than the chirality of the dopant and the helical structure of the CLC.

碩士
國立東華大學
化學系
96
A new method for chiral polyaniline synthesis was developed by using ionic liquid. In this experiment, 1-butyl -3-methyl imidazolium hexafluorophosphate (BMIM-PF6 ) , water immiscible ionic liquid ( IL) as interfacial media was used to produce chiral polyaniline. The optimal conditions for chiral polyaniline synthesis as follows: 0.54M polyacrylic acid(template) and 0.14M ammonium persulfate(oxidant) were dissolved in 2M CSA solution, 0.54M aniline was dissolved in ionic liquid. The proportion of aniline and ammonium persulfate was 4:1；the ratio of aniline and polyacrylic acid was 1:1. The best chirality of polyaniline was obtained at low temperature such as 4℃, and polymerized for 48hr. The morphology of polyaniline was cylinderal in Scanning Electron Microscope image. The ionic liquid was superior to organic solvent for chiral polyaniline synthesis. Ionic liquid can be recovered and used repeatly for at least 10 times.

碩士
國立東華大學
化學系
96
A new interfacial enzymatic method for chiral polyaniline was developed using 1-butyl -3-methyl imidazolium hexafluorophosphate (BMIM-PF6) water immiscible ionic liquid(IL) to aqueous/ionic liquid interface and to protect the enzymes under acidic reaction conditions. The better chirality of polyaniline was obtained in lower temperature, such as the 4 oC . The optimal conditions were as follow: 0.0016mole aniline monomer mixed with 1 mL 2M camphorsulfonic acid as aqueous layer and 6mg peroxidase dissolve in 1mL BMIM PF6 as IL layer and then incubated 36 hours statically at 4oC. The different optical spectrums were found under the same optical activity camphorsulfonic acid as dopant. It shows that the peroxidase is the main factor to induce the optical activity. IL could be reused repeatly for at least 5 times . however, the chirality of polyaniline will decrease comparing with the first time using of IL.

In der vorliegenden Dissertation geht es um die Synthese und Charakterisierung chiraler, redoxaktiver (Raumtemperatur-)Ionischer Flüssigkeiten basierend auf Ferrocen und der natürlich vorkommenden Aminosäure S-Prolin. Diese Baueinheiten sind entweder über eine Ether- oder über eine Esterverbrückung verknüpft. Auch der Anionenaustausch vom I– - zum CF3SO3– - sowie (CF3SO2)2N– -Salz (kurz NTf2–) wird dargelegt und der Einfluss des Anions auf den Schmelzpunkt der Verbindungen untersucht und diskutiert. Die Redoxaktivität wird durch das im Ferrocen enthaltene Fe II eingebracht, das reversibel zu Fe III oxidiert werden kann. Aufgrund des Pyrrolidin-Rings sind die dargestellten Verbindungen stets chiral und bilden nach der Quaternisierung mit Halogenalkanen Diastereomere, soweit die Alkylkette größer als Methyl ist. Das Diastereomerenverhältnis wurde mittels 1H-NMR-Spektroskopie und in einem Fall anhand von Röntgenpulverdiffraktogrammen durch Rietveld-Verfeinerung analysiert. Die Verbindungen wurden thermisch anhand simultaner thermischer Analysenund Tieftemperaturversuchen untersucht, die belegen, dass die Synthese von insgesamt sechs neuen Raumtemperatur-Ionischen Flüssigkeiten gelang. Davon basiert eine Verbindung, (1S2S)- und (1R2S)-2-[(Ferrocenylcarbonyl)oxy]methylen-N-methyl-N-pentylpyrrolidin-1-iumiodid, auf I– und fünf Verbindungen enthalten NTf2– als Gegenion. Das Diastereomerengemisch der Verbindungen (1S2S)- und (1R2S)-N-Butyl-2-[(ferrocenylcarbonyl)oxy]methylen-N-methylpyrrolidin-1-ium NTf2– besitzt den größten Flüssigkeitsbereich von -25 bis +263 °C und auch die höchste Zersetzungstemperatur aller hier dargestellten Verbindungen. Insgesamt werden in dieser Arbeit elf Einkristallstrukturanalysen vorgestellt, wobei es sich um drei Verbindungen des Typs FcCH2N(CH3)2(CnH2n+1)I (Fc = Ferrocenyl, n = 1,2,3), Ferrocenmonocarbonsäurechlorid, zwei ether- sowie fünf esterverbrückte Verbindungen handelt. Mikrokristalline Proben wurden mittels Röntgenpulverdiffraktometrie charakterisiert. Ergänzende Analysen wurden mittels UV-Vis- und IR-Spektroskopie sowie Massenspektrometrie und Elementaranalyse durchgeführt. Ein wichtiger Aspekt bei Ferrocenverbindungen ist das Redoxpotential, welches mittels Cyclovoltammetrie bestimmt wurde. Hierbei liegt das Formalpotential des Fe II /Fe III -Redoxpaars der etherverbrückten Verbindungen bei +0,05 V und bei den esterverbrückten Verbindungen unabhängig vom Anion bei +0,28 V vs. Ferrocen/Ferrocenium in Acetonitril. Bei den iodidhaltigen Verbindungen zeigt das I– -Ion ebenfalls eine Redoxaktivität bei E(0,f,Fc) = -0,18 V und 0,22V. Die Diffusionskoeffizienten der esterverbrückten Triflat- und NTf2– -Verbindungen liegen in der Größenordnung von 7·10−6 cm2/s und die heterogenen Geschwindigkeitskonstanten bei 0,01 cm/s.
The present dissertation deals with the synthesis and characterization of chiral, redoxactive room temperature ionic liquids (RTILs) based on ferrocene and the naturally occurring amino acid S-proline. These building blocks are coupled either via an ether- or an ester-bridge. The anion exchange from I– to CF3SO3– and (CF3SO2)2N– salts (abbreviated as NTf2–) is presented. The influence of the anion on the melting point of the compound is investigated and discussed. The redox activity is introduced into the molecule via the Fe II -containing ferrocenyl groups, which can be oxidized reversibly to Fe III . The synthesized compounds based on the pyrrolidine ring are chiral. After quaternization with alkyl halides, they form diastereomers in case of alkyl chains longer than methyl. The ratio of the different diastereomers was analyzed by 1H NMR spectroscopy and, in one case, by Rietveld refinement of the X-ray powder diffraction pattern. The thermal behavior of the compounds was studied by simultaneous thermal analysis and low temperature experiments. The results show the successful synthesis of six new RTILs. One of them is based on iodide ((1S2S)- and (1R2S)-2-[(ferrocenylcarbonyl)oxy]methylene-N-methyl- N-pentylpyrrolidine-1-ium iodide) and six RTILs contain NTf2– as counter ion. The diastereomeric mixture of compounds (1S2S)- and (1R2S)-N-butyl-2-[(ferrocenylcarbonyl)oxy]methylene-N-methylpyrrolidine-1-ium NTf2– exhibits the widest liquid range from -25 to +263 °C and the highest decomposition temperature of all compounds presented herein. Eleven single crystal structure analyses are presented. Three of them belong to compounds FcCH2N(CH3)2(CnH2n+1)I (with Fc = ferrocenyl and n = 1,2,3), then ferrocene monocarboxylic acid chloride, two of ether- as well as five ester-bridged compounds. Microcrystalline samples were characterized by X-ray powder diffractometry. Supplementary analyses by UV/Vis and IR spectroscopy as well as mass spectrometry and elemental analyses have been carried out. An important feature of ferrocene containing compounds is their redox potential which is determined with cyclic voltammetry. The formal potential of the Fe II /Fe III redox couple in the ether-bridged compounds is at +0.05 V and in the ester-bridged compounds independent from the type of anion at +0.28 V vs. ferro- cene/ferrocenium in acetonitrile. The I– anion shows as well redox activity with formal potentials at E(0,f,Fc) = -0.18 V and 0.22 V. The diffusion coefficients of the ester-bridged triflate and NTf2– compounds are in the order of 7·10−6 cm2/s, the heterogeneous rate constants in the order of 0.01 cm/s.