Modular Construction of Heterobiaryl Atropisomers and Axially Chiral Styrenes via All‐Carbon Tetrasubstituted VQMs

Abstract Here we report a new type of chiral all‐carbon tetrasubstituted VQMs generated via chiral phosphoric acids catalyzed nucleophilic addition of 2‐alkynylnaphthols to o ‐quinone methides or imines, which can be captured intramolecularly as a result of cycloaddition reaction. A new class of naphthyl‐2 H ‐chromenes bearing axially and centrally chiral elements and axially chiral quinone‐naphthols were prepared efficiently with good to excellent yields, diastereoselectivities and enantioselectivities. Noteworthy, the enantioselective cycloaddition of alkynylnaphthols with o ‐quinone methides proceeded via a [2+2] cycloaddition, followed by a retro‐4π‐electrocyclization and a 6π re‐cyclization. While the cycloaddition of alkynylnaphthols with imines proceeded via a sequential [2+4] cycloaddition and an auto oxidation reaction. Moreover, the obtained axially chiral naphthols can be converted into valuable phosphine ligands and other functional molecules.