ABSTRACT Inspired by the chemistry and biology of fluorine-containing molecules and pyrrolidinyl spirooxindoles, herein we report a highly diastereoselective [3+2] cycloaddition reaction of β,γ-unsaturated α-keto esters and N-2,2,2-trifluoroethylisatin ketimines in… Click to show full abstract
ABSTRACT Inspired by the chemistry and biology of fluorine-containing molecules and pyrrolidinyl spirooxindoles, herein we report a highly diastereoselective [3+2] cycloaddition reaction of β,γ-unsaturated α-keto esters and N-2,2,2-trifluoroethylisatin ketimines in the presence of the catalyst DABCO. The process enables efficient incorporation of CF3 groups into pharmaceutically important spiro[pyrrolidin-3,2′-oxindoles], bearing four contiguous stereogenic centers including one tetra substituted carbon, with high efficiency (up to 93% yield and >20:1 diastereomeric ratio). Moreover, using β,γ-unsaturated α-keto esters as the 2C building blocks in this reaction, which are different from other enone substrates such as chalcone and benzalacetone, further expanded their scope of applicability.
               
Click one of the above tabs to view related content.