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C. Lim:
"Chiral Cyclooctadiene Ligands For Rhodium Catalysis";
Betreuer/in(nen): M. Schnürch; Institut für Angewandte Synthesechemie, 2019; Abschlussprüfung: 19.06.2019.

Site-selective C-H functionalization has been under intensive research within the last decades
and today, many strategies are employed to achieve site-selectivity. Our group has previously
reported the direct alkylation of benzylic amines via C-H functionalization by utilizing olefins as
alkylating agents. In particular, an intrinsic pyridine-moiety was exploited as a directing group
to target a benzylic C-H bond. With optimized conditions in hand for the direct C(sp3)-H
activation with alkenes and quaternary ammonium salts as solid-olefin-surrogates, the focus
was appointed towards enantioselectivity.
To date, enantioselective C-H functionalization occupies a rather small quantity of the reported
methodologies. The lack of attention is quite striking as enantioselective C-H protocols are
potential methodologies for late-stage-modifications in pharmaceuticals and related topics.
This leaves room for further investigation and within this project, we are investigating the
stereochemical induction of the model reaction. To elucidate the feasibility, we were focusing
on ligand modification of the rhodium catalyst used in the alkylation reaction.
Our catalyst is a rhodium(I) dimer bearing 1,5-cyclooctadiene (cod) as ligand. This cod-ligand
is very common in catalytic systems and the application of such systems spans over a broad
variety of reaction types. Cycloocta-1,5-diene can be considered a standard ligand employed
in many systems, but chiral cod-ligands are not commonly applied.

https://publik.tuwien.ac.at/files/publik_287377.pdf