Metal-Catalyzed N-H and O-H Insertion from a-Diazocarbonyl Compounds

Transition-metal catalyzed X-H insertions from a-diazocarbonyl compounds represent one of the most efficient approaches to form C--X bonds. The presented thesis is based on the synthesis and application of a-diazocarbonyl compounds in metal-catalyzed N-H insertion and the chemoenzymatic synthesis of heterocycles via a [Cu]/[Rh] catalyzed intramolecular O-H insertion.

In the first part, a straightforward approach via the Wittig reaction, ?-Umpolung addition and diazo transfer reaction allowed the synthesis of unsaturated a-diazocarbonyl compounds with ease.

In the second part, the newly synthesized (R textsubscriptp)-pseudo-ortho [2.2]paracyclophane-based bisoxazoline ligands presented superior reactivity. The obtained d-amino a,ß-unsaturated carboxylic esters were used to synthesize hexahydroindoles, which are key intermediates in the synthesis route of Rostratin B-D.

Additional investigation of a-diazocarbonyl compounds led to the enzymatic synthesis of O-Heterocycles. With the employment of enantiopure starting material obtained from ketoreductase LbADH, the enantioselectivity of each diastereomer from the O-H insertion product have been effectivity improved.