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The present thesis deals with the interaction of CO2 and amines as molecular control factor to influence different kinds of selectivities in various catalytic processes. The reversibility of the Lewis acid-base reaction between CO2 and amines has been applied in numerous reaction and separation processes and chapter I gives a short overview of the different areas.
Up to date this interaction has not been used to steer the selectivity of a reaction and in this context, switchable solvents are applied in the selective homogeneous hydrogenation to steer the chemoselectivity in chapter II. The interaction between CO2 and amine was ensured by using the switchable solvent system of DBU and 1-hexanol. This switchable solvent system was characterised in detail in order to obtain a deeper insight on its effects in the reaction. Different homogeneous rhodium-complexes were evaluated as catalysts in the selective hydrogenation of 1,3-cyclohexadiene and 1,4-cyclohexadiene and the presence of various bases on the selectivity towards cyclohexene was investigated. As a result, the rhodium-complex [Rh(cod)(dppp)]BF4 was selected for further studies including concentration profiles, mechanistic considerations and catalyst recycling in the switchable solvent system.
