Organocatalytic Dearomatization of β‐Naphthols through a 1,6‐Conjugated Addition of Alkynyl 7‐Methylene‐7H‐indoles Formed In Situ

Abstract Organocatalytic dearomatization of β‐naphthols has been achieved via a 1,6‐conjugated addition of 2‐naphthols to alkynyl 7‐methylene‐7 H ‐indoles in situ generated from α‐(7‐indolyl)methanols. In the presence of racemic phosphoric acid, a series of tetrasubstituted allenes was obtained in high yields. Particularly, with the aid of chiral phosphoric acid, asymmetric dearomatization of β‐naphthols was investigated, affording axially chiral tetrasubstituted allenes with moderate enantioselectivity.