In the last century, no less than five nobel prizes have been awarded for the construction of carbon-carbon bonds : The Grignard reaction (1912), the Diels-Alder reaction (1950), the Wittig reaction (1979), Olefin metathesis (2005) and palladium cross-coupling reactions (2011). The latter two are transition metal catalyzed transformations and their impact on the synthesis of pharmaceutically active compounds, bulk chemicals, fine chemicals, high tech materials as well as agricultural chemicals has been phenomenal. These reactions have changed the way the scientific community views the science of synthesis. Unlike palladium, gold has long been considered to be an expensive and inert metal and therefore, research on Au catalysis was scarse until the begining of the new millenium. Once the scientific community realized the treasure trove of reactivity that gold had to offer, the number of chemical transformations as well as total syntheses involving Au(I)/Au(III) catalysis has sky rocketed. A methodology initially developped by Toste and coworkers has shown that intramolecular addition of a silyl enol ether on alkynes proceeds via a 5-exo¬-dig¬ process. In the first part of this thesis, we will discuss how the ancilary ligand on Au(I) species can influence pathway selectivity for these cyclizations, therefore opening the door to selective 6-endo-dig cyclizations to generate fused carbocycles. With biological processes as well as other competing processes becoming ever more efficient, the future of chemical synthesis is threatened. If it is to survive, the focus of new chemical transformations will have to be on the cost and the greeness of the process. In the second part of this thesis, we will demonstrate how Ag(I) and Cu(I) complexes can offer even better 6-endo-dig¬ selectivity than analogous Au(I) complexes. Silver is about 56 times less expensive than gold, and copper is about 453 times less expensive than gold. Due to the greatly increased selectivity as well as the diminished cost of the catalysts, we have provided access to an attractive 6-endo-dig¬ cyclization process.

Gold catalysis has attracted much attention within the chemical community in recent years, and its importance as a synthetic tool has only started to be uncovered. This thesis describes the development of a gold(I) catalyzed transformation and its application to the synthesis of a structurally unique Lycopodium alkaloid, Magellanine. Although there have been a few reports on the synthesis of the magellanane core to date, the approach described herein would represent a new and efficient strategy to construct the angularly fused tetracyclic core. The 5 exo dig/Prins reaction that would be the key step of the synthesis was first developed and studied on a model substrate, enabling the verification of the hypothesis that this transformation could indeed form the A and B rings of Magellanine and be applied to its synthesis. This reaction formed the tricyclic products in good yields and in good exo:endo ratios. The synthesis of Magellanine was undertaken, but problems of isomerization prevented the synthesis of the desired 5 exo dig/Prins substrate, which contained the C and D rings of Magellanine with a cis relationship at the ring junction. However, an almost identical substrate, save for a trans configuration between the C and D rings instead of the cis configuration, was prepared and served in further establishing the applicability of this methodology to the synthesis of Magellanine by successfully undergoing the 5-exo-dig/Prins reaction and generating the tetracyclic products. Studies of the steps following the key transformation were performed on the model substrate, allowing for the evaluation of these steps prior to their use in the synthesis. The results of the studies indicate a possible need to revisit the order in which the steps should be carried out. Promising solutions to the different obstacle encountered during the work are presented, demonstrating how the synthesis of Magellanine through a route featuring the 5-exo-dig/Prins cyclization is attainable.

I present numerical simulations of intensity and degree of polarization of light reflected by Earth-like exoplanets. The results are presented as a function of wavelength, and for a few different phase angles and a few different points on the planet. At this stage the aim is to show the working code and test a few different set ups of the star-planet system in order to find preferable configurations for observations. Not surprisingly, phase angle 90◦ shows the largest degree of polarization. For beneficial wavelength regions, visual light shows a larger overall degree of polarization, while NIR shows very clear absorption patterns in the degree of polarization, making detection of the atmospheric composition possible.

L'interférométrie annulante est une technique d'observation qui devrait permettre aux missions spatiales DARWIN (Agence Spatiale Eurpéeenne) ou TPF-I (NASA), de détecter et de caractériser spectralement l'atmosphère de planètes extra-solaires de type tellurique et de trouver d'éventuelles bio-signatures.<br /><br />Ce travail de thèse est une étude théorique et expérimentale de cette technique. Après une présentation du contexte astrophysique justifiant l'utilisation de tels instruments, ce manuscrit se focalise sur le problème de l'obtention expérimentale des niveaux d'extinction interférométrique requis pour la détection de planètes (10-5) ainsi que leur stabilisation (elle aussi indispensable à la détection de planètes).<br /><br />Un banc banc interférométrique : NULLTIMATE a été conçu pour la caractérisation expérimentale de déphaseurs achromatiques, l'un des composants optiques essentiels d'un interféromètre annulant. Cet interféromètre de laboratoire doit fonctionner dans la bande spectrale du futur instrument : 618 µm. Il a été conçu pour fonctionner à basse température. Il devrait permettre de caractériser quatre types de déphaseurs achromatiques différents, à la fois en mesurant des niveaux d'extinction élevés (de l'ordre de 10-5) et en mesurant le déphasage introduits par ces déphaseurs en fonction de la longueur d'onde. Ce banc pourra enfin être un bon laboratoire pour tester des techniques de stabilisation de l'extinction.

In the last century, no less than five nobel prizes have been awarded for the construction of carbon-carbon bonds : The Grignard reaction (1912), the Diels-Alder reaction (1950), the Wittig reaction (1979), Olefin metathesis (2005) and palladium cross-coupling reactions (2011). The latter two are transition metal catalyzed transformations and their impact on the synthesis of pharmaceutically active compounds, bulk chemicals, fine chemicals, high tech materials as well as agricultural chemicals has been phenomenal. These reactions have changed the way the scientific community views the science of synthesis. Unlike palladium, gold has long been considered to be an expensive and inert metal and therefore, research on Au catalysis was scarse until the begining of the new millenium. Once the scientific community realized the treasure trove of reactivity that gold had to offer, the number of chemical transformations as well as total syntheses involving Au(I)/Au(III) catalysis has sky rocketed. A methodology initially developped by Toste and coworkers has shown that intramolecular addition of a silyl enol ether on alkynes proceeds via a 5-exo¬-dig¬ process. In the first part of this thesis, we will discuss how the ancilary ligand on Au(I) species can influence pathway selectivity for these cyclizations, therefore opening the door to selective 6-endo-dig cyclizations to generate fused carbocycles. With biological processes as well as other competing processes becoming ever more efficient, the future of chemical synthesis is threatened. If it is to survive, the focus of new chemical transformations will have to be on the cost and the greeness of the process. In the second part of this thesis, we will demonstrate how Ag(I) and Cu(I) complexes can offer even better 6-endo-dig¬ selectivity than analogous Au(I) complexes. Silver is about 56 times less expensive than gold, and copper is about 453 times less expensive than gold. Due to the greatly increased selectivity as well as the diminished cost of the catalysts, we have provided access to an attractive 6-endo-dig¬ cyclization process.

Gold catalysis has attracted much attention within the chemical community in recent years, and its importance as a synthetic tool has only started to be uncovered. This thesis describes the development of a gold(I) catalyzed transformation and its application to the synthesis of a structurally unique Lycopodium alkaloid, Magellanine. Although there have been a few reports on the synthesis of the magellanane core to date, the approach described herein would represent a new and efficient strategy to construct the angularly fused tetracyclic core. The 5 exo dig/Prins reaction that would be the key step of the synthesis was first developed and studied on a model substrate, enabling the verification of the hypothesis that this transformation could indeed form the A and B rings of Magellanine and be applied to its synthesis. This reaction formed the tricyclic products in good yields and in good exo:endo ratios. The synthesis of Magellanine was undertaken, but problems of isomerization prevented the synthesis of the desired 5 exo dig/Prins substrate, which contained the C and D rings of Magellanine with a cis relationship at the ring junction. However, an almost identical substrate, save for a trans configuration between the C and D rings instead of the cis configuration, was prepared and served in further establishing the applicability of this methodology to the synthesis of Magellanine by successfully undergoing the 5-exo-dig/Prins reaction and generating the tetracyclic products. Studies of the steps following the key transformation were performed on the model substrate, allowing for the evaluation of these steps prior to their use in the synthesis. The results of the studies indicate a possible need to revisit the order in which the steps should be carried out. Promising solutions to the different obstacle encountered during the work are presented, demonstrating how the synthesis of Magellanine through a route featuring the 5-exo-dig/Prins cyclization is attainable.

Kainic acid has been used for nearly 50 years as a tool in neuroscience due to its pronounced neuroexcitatory properties. However, the significant price increase of kainic acid resulting from the disruption in the supply from its natural source, the alga Digenea Simplex, as well as inefficient synthesis of kainic acid, call for the exploration of functional mimics of kainic acid that can be synthesized in a simpler way. Aza kainoids analog could be one of them. The unsubstituted aza analog of kainoids has demonstrates its ability as an ionotropic glutamate receptor agonist and showed affinity in the chloride dependent glutamate (GluCl) binding site. This opened a question of the importance of the presence of one nitrogen or both nitrogens in the aza kainoid analogs for binding to glutamate receptors. Therefore, two different pyrrolidine analogs of kainic acid, trans-4-(carboxymethyl)pyrrolidine-3-carboxylic acid and trans-2-carboxy-3-pyrrolidineacetic acid, were synthesized through multi-step sequences. The lack of the affinity of both pyrrolidine analogs in GluCl binding site indicated that both nitrogens in aza kainoid analogs are involved in hydrogen bonding with receptors, significantly enhancing their affinity in GluCl binding site. Another potential functional mimic of kainic acid is isoxazolidine analogs of kainoids whose skeleton can be constituted directly via a 1, 3 dipolar cycloaddition as the key step. The difficulty in synthesizing N-unsubstituted isoxazolidines when applying such common protecting groups as alkyl, phenyl and benzyl groups, and the requirement of a desired enantioselectivity due to the three chiral ceneters in kainic acid, pose great challenges. Hence, several different protected nitrones were studied to establish that diphenylmethine nitrone may be a good candidate as the dipole in that the generated isoxazolidines can be deprotected in mild conditions with high yields. Our investigations also indicated that the exo/endo selectivity of the 1, 3 dipolar cycloaddition can be controlled by Lewis acids, and that the application of a directing group in dipolarophiles can accomplish a satisfied enantioselectivity. Those results demonstrated the synthesis of isoxazoldines analogs of kainic acid is very promising.

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Denna rapport omfattar ett examensarbete skriven för Husqvarna AB av Hugo Klippfors och Olle Frank. Arbetet ägde rum under vårterminen 2023 på Jönköpings Tekniska Högskola. Examensarbetet är den avslutande delen på skribenternas högskoleingenjörsutbildning inom maskinteknik med inriktning produktutveckling och design.Under de senaste åren har aktiviteten på marknaden kring exo-skelett ökat. Både passiva och aktiva exo-skelett till flera olika marknader som logistik, hantverk och inommedicinbranschen existerar, där ett exo-skeletts funktion är att ge ergonomiskt stöd åt muskler och leder. Skogshuggare är ett yrke som är drabbat av bland annat ländryggsbesvär och trots att motorsågar ändrat design och vikten blivit lättare med åren, har besvären kvarstått. Det finns därför behov av förändring på marknaden. På Chalmers tekniska högskola skrevs 2022 ett examensarbete i samarbete med Husqvarna. Målet var att undersöka om exo-skelett skulle kunna minska risken för skador och ett koncept togs fram. Lösningen i fråga tas vid i detta examensarbete, med målet att utvärdera konceptet samt utveckla en prototyp, för att Husqvarna ska kunna utvärdera om detta är något för deras framtida sortiment.Rapporten följer metoder med en produktutvecklingsprocess som innefattar planering, förstudie, produktframtagning, utvärdering med konceptval samt prototypframtagning. Processens metoder och bakomliggande teorier definieras i rapportens gång, som sedan ligger till grund för slutresultatet. De krav och begränsningar som produkten ska utgå ifrån har tagits fram tillsammans med Husqvarna. Detta genom en marknadsanalys ochett antal fokusgrupper som har hållits tillsammans med grupper som Quality Assurance på företaget. Även intervjuer har hållits, samt en konkurrents produkt har testats och evaluerats.Arbetet resulterar slutligen i en färdig prototyp som avlastar ländryggen vid framåtlutande bål. Prototypen ska kunna testas ute i fält av skogshuggare och vidareutveckling för Husqvarna ges förslag på.

Lyconadin A (1) is a structurally unique Lycopodium alkaloid with antitumor properties, isolated from the club moss Lycopodium complanatum. We are developing a synthetic route to 1 based on a novel 7-exo-trig/6-exo-trig acyl radical cascade cyclization. The synthesis of model acyl radical cascade precursor 23 will be presented. Key features of this synthesis include the suppression of competing elimination during the alkylation of a hindered phenethyl bromide and the use of a lactone as a precursor to a compound bearing two differentially protected primary alcohols. An account of our studies on the model acyl radical cascade cyclization (23 to 24 above) will also be given, including a stereochemical analysis of the product. Our findings have been applied to develop a more detailed stereoselective synthetic plan for Lyconadin A (1).