Organocatalytic Enantioselective Cycloetherifications Using a Cooperative Cation-Binding Catalyst

다국어 초록 (Multilingual Abstract)

<P>A highly enantioselective cycloetherification strategy for the straightforward synthesis of enantioenriched tetrahydrofurans, tetrahydropyrans, and oxepanes using Song’s cation-binding oligoEG catalyst and KF as the base is demonstrated. A wide range of <I>ε-</I>, <I>ζ-</I>, and η-hydroxy-α,β-unsaturated ketones were cyclized to the corresponding five-, six-, and seven-membered chiral oxacycles with high enantiopurity. This remarkably successful catalysis can be ascribed to systematic cooperative cation-binding catalysis in a densely confined supramolecular chiral cage generated <I>in situ</I> from the chiral catalyst, substrate, and KF.</P>
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