Summary: | Biisoquinolines have been known to be good chelating agents. Four chiral
biisoquinoline-based ligands were synthesized and used for asymmetric catalytic addition
of diethylzinc to ketones. The reaction was tested for optimal conditions – type of
ligands, catalyst loading, temperature, type of solvent, and the reaction time – with
acetophenone as substrate. Under the optimum reaction conditions obtained, the catalytic
reaction was carried out with other various ketones to see the influence of changes to
ketone structures on the enantiomeric excess and yield of the products. HPLC analysis
have shown encouraging results of moderate to excellent enantioselectivities of up to
90%, thus promoting future investigations in the application of the synthesized ligands to
other ketones and even other types of asymmetric additions.
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