Bidirectional enantioselective synthesis of bis-benzofuran atropisomeric oligoarenes featuring two distal C-C stereogenic axes

Abstract

We report the bidirectional enantioselective synthesis of bis-benzofuran atropisomeric oligoarenes featuring two distal C-C stereogenic axes obtained by a two-fold central-to-axial chirality conversion upon oxidative aromatization. The key enantioenriched centrally chiral bis-dihydrobenzofuran precursors were synthesized via a bidirectional diastereo- and enantio-selective organocatalyzed domino reaction between simple achiral and easily accessible dihydroxylated aromatics and chloronitroalkenes. Moreover, the stereodivergent nature of the methodology was established by synthesizing both diastereomers of a non-symmetrically functionalized bis-axially chiral oligoarene.