Chiral Brønsted Acid‐Catalyzed Asymmetric 1,4‐Addition of Benzofuran‐Derived Azadienes with 3‐Substituted indoles
Zhou Ji, Tian‐Zhen Li, Yu‐Wen Sun, Bai‐Xiang Du, Wei Tan, Feng Shi
Abstract
Abstract A chiral phosphoric acid‐catalyzed asymmetric 1,4‐addition of benzofuran‐derived azadienes with 3‐substituted indoles has been established, which offered enantioenriched tri(hetero)arylmethane products in generally good yields (up to 98 %) and high enantioselectivities (up to 99 : 1 er). This reaction has not only realized the application of chiral phosphoric acid as a competent catalyst in the asymmetric transformations of benzofuran‐derived azadienes, but also has accomplished the task of developing chiral Brønsted acid‐catalyzed asymmetric 1,4‐additions of benzofuran‐derived azadienes, which will enrich the research contents of chiral phosphoric acid catalysis and the chemistry of benzofuran‐derived azadienes.