The development of peptides as catalysts for preparing optically active molecules is an ongoing investigation. Efforts at expanding the use of peptides are explored in two ways: investigating novel reactions in which peptides can act as asymmetric catalysts and through expanding the substrate scope of peptides in performing kinetic resolutions. Attempts at furthering the reaction scope of acylsulfonamide-containing peptides to act as BrØnsted acids through promoting the attack of 7-methyl oct-6-ene-1-tosylaziridine (9) by an internal π-nucleophile are discussed herein. Also reported is the use of pentameric peptides containing a π(-methyl)histidine residue in the kinetic resolution of the primary alcohol 4-hydroxymethyl cyclopent-2-enone (76) and the secondary aliphatic alcohol 2- pentanol. Moderate selectivities were observed in the kinetic resolution of 4-hydroxymethyl cyclopent-2-enone (76) and promising results were obtained in the initial screening of catalysts for the resolution of 2-pentanol. / Thesis (MS) — Boston College, 2008. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Chemistry.

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Com o aumento da consciência global sobre os riscos do Aquecimento do Planeta e de suas possíveis causas ficou claro que é necessário desenvolver ou adaptar processos industriais de maneira a aproveitar dejetos como o CO2. Dentre as formas de se aproveitar o CO2, destaca-se a ciclo-adição aos epóxidos, com a formação de ciclocarbonatos. A reação é tecnologicamente interessante, pois ciclocarbonatos possuem diversas aplicações como solventes polares apróticos, eletrólitos e matéria prima para compostos como purinas, carbamatos, glicóis, policarbonato e outros. Para que a reação ocorra em tempo e condições viáveis, há a necessidade de se trabalhar com catalisadores. Foram reportados muitos catalisadores ao longo dos anos. Dentre os catalisadores mais comumente utilizados, destacam-se os sais orgânicos. Porém o estudo sobre modelos cinéticos e mecanismo de reação ainda carecem de mais atenção. Desta forma este trabalho propõe-se a estudar esta parte, através de experimentos cinéticos, modelos teóricos e cálculos de química quântica. Para isto escolheu-se estudar a ação catalítica do brometo de 1-propil-4-azo-1-azôniobiciclo[2,2,2]octano (P-DABCO) frente a um catalisador bem descrito na literatura, o brometo de tetrapropilamônio (TPA). / Nowadays mankind are becoming more aware about Global Warming risks and its possible causes. With that in mind, it is necessary to develop or to adapt industrial processes to use some wastes like CO2. One of the best strategies to utilize CO2 is to convert it to cyclic carbonate through cyclic addition reaction to epoxides. This reaction is important because cyclic carbonates have other useful applications. For example, they can be used as polar aprotic solvents, electrolytes and as starting material for other compounds like purine, carbamates, glycols, polycarbonate, among others. However, the cyclic addition reaction must be catalyzed so as to get the desired product in short possible time and under soft conditions. Many catalysts have been reported in the literature that can be used for the cyclic addition reaction, with the organic salts being very common ones. Most of these reports focus on the efficiency of the catalyst and little attention has been paid to the reaction kinetics models and reaction mechanisms. Thus, we intend to study this part. For this purpose, we will do kinetics experiments, theoretical models and quantum chemistry calculation. The 1-alkyl-4-aza-1-azaniabicyclo[2.2.2]octyl bromide was chosen to this work and will be compared with tetrapropylammonium bromide that is known in the literature.

Com o aumento da consciência global sobre os riscos do Aquecimento do Planeta e de suas possíveis causas ficou claro que é necessário desenvolver ou adaptar processos industriais de maneira a aproveitar dejetos como o CO2. Dentre as formas de se aproveitar o CO2, destaca-se a ciclo-adição aos epóxidos, com a formação de ciclocarbonatos. A reação é tecnologicamente interessante, pois ciclocarbonatos possuem diversas aplicações como solventes polares apróticos, eletrólitos e matéria prima para compostos como purinas, carbamatos, glicóis, policarbonato e outros. Para que a reação ocorra em tempo e condições viáveis, há a necessidade de se trabalhar com catalisadores. Foram reportados muitos catalisadores ao longo dos anos. Dentre os catalisadores mais comumente utilizados, destacam-se os sais orgânicos. Porém o estudo sobre modelos cinéticos e mecanismo de reação ainda carecem de mais atenção. Desta forma este trabalho propõe-se a estudar esta parte, através de experimentos cinéticos, modelos teóricos e cálculos de química quântica. Para isto escolheu-se estudar a ação catalítica do brometo de 1-propil-4-azo-1-azôniobiciclo[2,2,2]octano (P-DABCO) frente a um catalisador bem descrito na literatura, o brometo de tetrapropilamônio (TPA). / Nowadays mankind are becoming more aware about Global Warming risks and its possible causes. With that in mind, it is necessary to develop or to adapt industrial processes to use some wastes like CO2. One of the best strategies to utilize CO2 is to convert it to cyclic carbonate through cyclic addition reaction to epoxides. This reaction is important because cyclic carbonates have other useful applications. For example, they can be used as polar aprotic solvents, electrolytes and as starting material for other compounds like purine, carbamates, glycols, polycarbonate, among others. However, the cyclic addition reaction must be catalyzed so as to get the desired product in short possible time and under soft conditions. Many catalysts have been reported in the literature that can be used for the cyclic addition reaction, with the organic salts being very common ones. Most of these reports focus on the efficiency of the catalyst and little attention has been paid to the reaction kinetics models and reaction mechanisms. Thus, we intend to study this part. For this purpose, we will do kinetics experiments, theoretical models and quantum chemistry calculation. The 1-alkyl-4-aza-1-azaniabicyclo[2.2.2]octyl bromide was chosen to this work and will be compared with tetrapropylammonium bromide that is known in the literature.

Nanopartiklar (NP) erbjuder unika möjligheter för medicinska tillämpningar, inklusive kontrollerad frisättning av cancerläkemedel, användning som bildkontrast vid avbildningsprocedurer eller hypertermisk behandling av cancerceller. Flash nanoprecipitation (FNP) producerar NPs för att kombinera dessa tillämpningar i en snabb, billig och skalbar beläggningsprocess. Användning av FNP med en Multi-Inlet Vortex Mixer (MIVM) är en lovande metod för att enkelt belägga hydrofoba oljesyra järnoxid NP (IONP) med olika biokompatibla block-copolymerer. Amfifila block-copolymerer baserade på hydrofil polyetylenglykol (PEG) och hydrofob poly(laktid) (PLA), poly(laktid-co-glykolid) (PLGA) eller poly(kaprolakton) (PCL) syntetiserades framgångsrikt. Den organiska katalysatorn 1,8-diazabicyclo[5.4.0]undec-7-en (DBU) användes för att öka biokompatibiliteten hos de resulterande polymererna PEG-PLA, PEG-PL7,5KG2,5KA och PEG2K-PCL2K. Syntes av hydroxylterminerad poly(akrylsyra) (PAA-OH) följt av polymerisation med PLGA prövades. De amfifila blockpolymererna användes i kombination med stabilisatorn polysorbat 80 (Tween80®) i FNP för att bilda nakna polymera NP med en MIVM som reaktor. DLS och STEM bekräftade partikelstorlekar mellan 50 - 100 nm. Tillsatsen av 13 ± 2 nm hydrofoba oljesyra-IONPs gav en ökning av partikelstorleken samt en ökning av partikelstabiliteten över tid. STEM-bilder visade att enstaka IONPs fästs på utsidan av de polymera NPs. Hydrofoba interaktioner mellan polymeren och oleinsyra-IONPs är möjliga. För att uppnå inkapsling av oljesyra-IONPs bör justeringar av processparametrarna för FNP övervägas i framtida forskning. Ytterligare experiment krävs för att utforska möjliga läkemedelstillsatser, frisättningsmekanismer och hypertermi hos de polymerbelagda IONP-partiklarna. / Nanoparticles (NPs) offer unique possibilities for medical applications, including the controlled release of cancer drugs, the use as imaging contrast during imaging procedures or the hyperthermic treatment of cancer cells. Flash nanoprecipitation (FNP) produces NPs to combine these applications in a fast, cheap, and scalable coating process. The use of FNP with a Multi-Inlet Vortex Mixer (MIVM) is a promising method to easily coat hydrophobic oleic acid iron oxide NPs (IONPs) with various biocompatible block-copolymers. Amphiphilic block-copolymers based on hydrophilic polyethylene glycol (PEG) and hydrophobic poly(lactic acid) (PLA), poly(lactic-co-glycolic acid) (PLGA) or poly(caprolactone) (PCL) were successfully synthesized. The organic catalyst 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) was used to increase biocompatibility of the resulting polymers PEG-PLA, PEG-PL7.5KG2.5KA and PEG2K-PCL2K. The synthesis of hydroxyl terminated poly(acrylic acid) (PAA-OH) followed by the polymerization with PLGA was attempted. The amphiphilic block-copolymers were used in combination with the stabilizer polysorbate 80 (Tween80®) in FNP to form bare polymeric NPs using a MIVM as the reactor. DLS and STEM confirmed particle sizes between 50 - 100 nm. The addition of 13 ± 2 nm hydrophobic oleic acid IONPs yielded an increase in particle size as well as increase in particle stability over time. STEM images showed attachment of single IONPs to the outside of the polymeric NPs. Hydrophobic interactions between the polymer and oleic acid IONPs are possible. To achieve encapsulation of the oleic acid IONPs, adjustments to the process parameters of FNP should be considered in future research. Additional experiments are required to explore possible drug addition, release mechanisms and hyperthermia behavior of the polymer coated IONPs particles.