Experimental data of the molar excess enthalpy of 17 binary alkanol+amine mixtures are presented obtained at 298.15 K by using an isoperibolic titration calorimeter (LKB 8700). The data are used for testing the ERAS model which accounts for self association and cross association of mixtures containing hydrogen bonds in the liquid state as well as for free volume effects based on an equation of state which incorporates the chainlike association of the molecules. Self association and cross association enthalpies of the hydrogen bonds are obtained as well as association constants providing an insight into the intermolecular structure of this kind of liquid mixtures.

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Ein additiver Ansatz auf der Grundlage der Summenformel wurde genutzt, um die Verdampfungsenthalpie einer ionischen Flüssigkeit zu berechnen. Die Enthalpie wird in einen Hauptbeitrag für die enthaltenen Elemente (ohne Beachtung ihrer Position in Kation oder Anion) und einen Korrekturterm für besondere Strukturmerkmale wie CF3‐Gruppen oder Ringe aufgespalten.

A diagnostic tool for checking the consistency of thermochemical data of tris(beta-diketonato)metal complexes is developed.

Cellulose-derived platform chemicals offer viable substitutes for most petroleumbased polymers and also enable the development of novel functional materials. In the focus of this work are thermophysical and thermochemical studies of dihydro-levoglucosenone (Cyrene) and levoglucosenone, which are considered as potential "green" replacements for industrial polar aprotic solvents. The densities, viscosities, absolute vapor pressures, and combustion energies of cyrene and levoglucosenone were measured in this work. The thermodynamic properties of levoglucosan derivatives are reliable for thermochemical calculations and used to calculate reaction enthalpies of valorization of the cellulose component of biomass. These enthalpies of reaction are useful in the further optimization and development of sustainable syntheses of commodity chemicals and fuels from biomass. The data provided in this work will aid researchers and engineers as the use of these new solvents grows.

Indole and methylindole are heterocyclic aromatics, which can be hydrogenated and used for hydrogen storage. A huge advantage of heterocyclic components compared to homocyclic aromatics is the lower enthalpy of reaction for hydrogen release by dehydrogenation. In this study, thermochemical properties of indole and 2-methylindole and its partially and fully hydrogenated derivatives have been determined. Hydrogenation of indoles is a two-step reaction, which is highly influenced by reaction thermodynamics. High precision combustion calorimetry was used to measure enthalpies of formation of indole derivatives. The gas-phase enthalpies of formation were derived with the help of vapor pressure measurements. The high-level quantum-chemical methods were used to establish consistency of the experimental data. The standard molar thermodynamic functions of formation (enthalpy, entropy, and Gibbs energy) of indole derivatives were derived. The results showed that the partially hydrogenated species, 2-methylindoline, tends to dehydrogenate easily under hydrogen release conditions. Thus, indoline is only expected in trace amounts in the respective reaction mixture.

Within the last decade the Carbonate Based Ionic liquid Synthesis (CBILS®) has developed towards a widely applicable, greener and halogen free process for the industrial production of ionic liquids. A large number of diverse starting materials have been screened experimentally, to explore the structural limits of the core reaction step, which is the quaternization of nitrogen, phosphor or sulfur based nucleophiles with carbonic acid dialkyl or diaryl esters to the corresponding quaternary alkyl- or arylcarbonates. In order to overcome the large experimental effort of empirical screening, a practical method based on quantum-chemical calculation has been developed for an assessment of feasibility of chemical reactions. This method has been successfully tested with 16 typical CBILS® reactions by calculation of their thermodynamic functions. Thermodynamic equilibrium constants as a measure for the practical yield of the CBILS® reactions at 298 K and 393 K have been determined for both the gaseous state and the liquid state. The method has been evaluated by comparison of the theoretical results with experimental data and it can be considered as the powerful tool to reduce "trial and failure" for the industrial application of the CBILS® process.

Höhere Überlebenschancen für teure Katalysatoren: Der Einsatz von Propylencarbonat als Lösungsmittel bei der iridiumkatalysierten Hydrierung nichtfunktionalisierter Olefine ermöglicht ein effizientes Katalysatorrecycling durch Bildung von Zweiphasengemischen mit unpolaren Lösungsmitteln wie n‐Hexan.