Novel chemo-enzymatic strategies for asymmetric aldol-type reactions using in situ formed acetaldehyde in deep eutectic solvents

This Ph.D. thesis deals with the question, if an in situ generation of acetaldehyde is advantageous for chosen catalytic processes. Starting point of this idea is a slow release of highly reactive acetaldehyde by transesterification reactions of vinyl esters with the enzyme CALB. Another approach is the oxidation by alcohol dehydrogenases. As benchmark reaction for detecting acetaldehyde, the cross coupling aldol reaction with p-nitrobenzyaldehyde catalyzed by proline derivatives was chosen. Overall, this system describes a chemo-enzymatic one-pot multi-step reaction. One of the key factors was the use of a new solvent class: A deep eutectic solvent (DES). Under all tested solvents, this solvent class delivered best results. A deep eutectic solvent is a mixture of molten salts which has a lower melting point than those observed for the single components. An important criteria for counting to the class of DES is a melting point of