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Five-membered cyclic sulfamidates are very valuable electrophiles in organic synthesis and readily used on a multikilogram scale. However, their thermal degradation is underreported and might lead to unforeseen and undesirable safety events. In addition, ring or nitrogen substitution can have a tremendous influence on cyclic sulfamidate reactivity toward bases and therefore impact the overall safety assessment of a process. An understanding of such behavior is therefore of high importance in the industry while designing a synthetic route, as a change of, e.g., a protecting group can increase the thermal safety of a step on scale. We report herein the thermal degradation investigation as well as the structure-related reactivity exploration of cyclic sulfamidates, including their use in combination with strong bases. The design of a predictive model to rapidly assess the thermal hazard based on collected data and selected molecular descriptors is also presented.

We report a simple synthetic route based on electroless deposition (galvanic displacement) and natural lithography to synthesize organized Au nanoparticles (NPs). We will study the influence of different experimental parameters (time, temperature, pH and additives) on the synthetic process. We show for the first time the formation of organized extended domains of Au nanorings using gelatin as an additive. A wide range of applications can be envisaged for these nanostructures, as for instance chemical- and bio-sensors using the SERS effect.

A combinatorial chemical beam epitaxy technique was used to optimize deposition of {001} lithium niobate thin films on {001} sapphire substrates. Lithium tert-butoxide and niobium tetra-ethoxy di-methyl-amino-ethoxide were used as precursors. The highest quality films obtained exhibited rocking curve full-width at half-maximum values of about 0.03deg and lithium contents larger than estimated by Raman spectroscopy. High-resolution transmission electron microscopy observations revealed that the lithium niobate film consists of a buffer layer (thickness ) with a high density of defects above which the epitaxial lithium niobate film was obtained.

Before scaling up to production, it is of high importance to evaluate the potential of a reaction to lead to an undesired thermal degradation event. The use of a large amount of compounds is usually required for a reliable calorimetry study. In this work, we report the development of a milliliter-scale reaction calorimeter for reaction screening applications. The setup was designed using laboratory equipment and characterized and validated with routine experiments. The results were sufficiently accurate enabling us to observe trends in the measured reaction enthalpies of a family of compounds reacting with strong bases as a function of the compounds' structures.. The use of the microscale tailor-made calorimeter is considered very valuable for potentially highly energetic reactions since reaction calorimetry studies can be performed accurately and safely with small amounts of valuable materials.

Two (−)‐5,6‐pinene‐bipyridine moieties connected by a para‐xylylene bridge (so‐called chiragen‐type ligands), (−)‐L1, undergo self‐assembly upon reaction with equimolar amounts of CuIto form enantiopure circular hexanuclear P‐helicates. If both enantiomers of L1 are used, mixtures of Pand Mhexanuclear helicates are exclusively obtained through a complete chiral recognition; that is, no mixing of the (+) and (−) ligands, respectively, occurs upon complexation. This was proven by a) NMR spectroscopy where identical spectra to those for complexes with the enantiomerically pure ligands were obtained and b) circular dichroism (CD) spectroscopy. The reaction is completely changed by the use of the corresponding meso‐L1. Instead of well‐defined species, oligomeric mixtures are observed, a result demonstrating the crucial role played by ligand chirality in self‐assembly processes. Structural variations on the chiral ligand L1, such as a meta‐xylylene bridge instead of a para‐xylylene one (in L4) or four pinene groups instead of two (in L5 and L6), favor nondiscrete coordination assembly.

A combinatorial chemical beam epitaxy technique was used to optimize deposition of {001} lithium niobate thin films on {001} sapphire substrates. Lithium tert-butoxide [Li(OBut)]and niobium tetra-ethoxy di-methyl-amino-ethoxide [Nb(OEt)4(dmae)]were used as precursors. The highest quality films obtained exhibited rocking curve full-width at half-maximum values of about 0.03° and lithium contents {[Li]∕[((Li))+(Nb)]}larger than 48(mol%)estimated by Raman spectroscopy. High-resolution transmission electron microscopy observations revealed that the lithium niobate film consists of a buffer layer (thickness <8nm) with a high density of defects above which the epitaxial lithium niobate film was obtained.