DMAP Promoted Tandem Addition Reactions Forming Substituted Tetrahydroxanthones

Abstract

Substituted tetrahydroxanthones are constructed using a DMAP-promoted tandem nucleophilic addition process. The reaction yields range from 39% to 73%. Disubstituted tetrahydroxanthones are generated as a ∼2.3:1 mixture of diastereomers favoring the formation of the <i>trans</i>-isomer