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Electrochemistry is a relatively old field of research for chemistry which has recently undergone a revival in the field of organic synthesis, due to increased attention for the unique reactivity of radicals and the possibilities of radical transformations for late-stage functionalization. By applying a potential difference across electrodes immersed in a reaction medium, electrons can be used as green and traceless reagents to perform transformations in a mild fashion at room temperature, giving access to novel chemistries without the need for chemical oxidants or reductants. These insights can be applied to many fields of chemistry where organic synthesis is of importance, including in the design and synthesis of pharmaceutically relevant compounds. Sulfonamides represent the largest class of sulfur-containing pharmaceuticals. They are usually synthesized from sulfonyl chlorides and amines. However, for the synthesis of sulfonyl chlorides, harsh conditions and reagents are usually required. In this thesis, a novel route towards the synthesis of sulfonamides is explored using electrochemistry. Initially, we sought to develop a protocol for the synthesis of sulfonamides starting directly from thiols and amines, of which many are commercially available, excluding the need for the synthesis or availability of the sulfonyl chloride. The optimization of the reaction is presented in this thesis, as well as a preliminary exploration of the scope of the transformation in which different aromatic thiols were coupled with an amine, and different amines were coupled with the simple aromatic thiol, thiophenol. One drawback of electrochemistry is the requirement for stoichiometric amounts of electrolyte and the fact that reactions occur at the surface of the electrode. For this reason, the reactions are strongly mass-transfer limited. Using flow chemistry, a technique where reactions are performed in reactors with channels of small dimensions, the reaction can be drastically accelerated. The reaction was performed in a novel electrochemical microreactor designed by the group in Eindhoven. A batch procedure was also developed using a simple electrochemical cell which can be constructed for a cost of less than 200€. By using flow chemistry, the reaction can be drastically accelerated from 18 hours of reaction time under batch conditions to 5 minutes under flow conditions. Moreover, the amount of electrolyte can be decreased ten-fold when going from batch to flow, highlighting the environmental benignity of the methodology.

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Gels have been around for centuries. However, it is not until recently that a specific class of gels, low molecular weight gels, gained significant attention amongst scholars. This is due to their potential in many high tech applications such as tissue engineering, drug delivery, waste removal and so on. Unfortunately, their discovery is serendipitous, which makes the design of these materials problematic. Gels typically consist of two substances: a fluid and a gelator. The latter forms a network that immobilises the fluid leading to the extraordinary features of a gel. The inability to predict gelation is often assigned to the inaccurate description of the interactions between these gelator molecules. Therefore, this work aimed to rationalise the gelation behaviour by gaining insight into the crucial interactions. To achieve this, a unique combination of experiments and computational calculations was used on a set of bis-urea based low molecular weight hydrogelators. A library of compounds was synthesised. To assess their gelation performance, vial inversion tests and rheology measurements were performed. From this, three efficient new low molecular weight hydrogelators were discovered. Moreover, it was also observed that the type of gelation procedure significantly affected their performance. Additionally, a set of computational calculations was performed on different scales, which ultimately formed a bottom-up approach. This method identified the importance of two non-covalent hydrogen bonding interactions, hydrogen bonding between two urea moieties and hydrogen bonding between a urea moiety and a pyridine ring. Remarkably these interactions appeared intra- as well as intermolecular. With these results, the gelation performance of the studied compounds was partially rationalised. As such, this study is a first step towards a smarter design of low molecular weight gelators.