Although asymmetric phosphine catalysis is a powerful tool for the construction of various chiral carbon centers, its synthetic potential toward an enantioenriched atropisomer has not been explored yet. Reported herein is a phosphine-catalyzed atroposelective (4+2) annulation of delta-acetoxy allenoates and 2-hydroxyquinone derivatives. The reaction provides expedient access to aryl-naphthaquinone atropisomers by the de novo construction of a benzene ring. The two functionalities of the catalyst, a tertiary phosphine (Lewis base) and a tertiary amine (Bronsted base), cooperatively enable this process with high regio- and enantioselectivities.
[1]Changzhou Univ, Sch Petrochem Engn, Jiangsu Key Lab Adv Catalyt Mat & Technol, 1 Gehu Rd, Changzhou 213164, Peoples R China.
[2]Shanghai Univ Tradit Chinese Med, Res Ctr Chiral Drugs, Innovat Res Inst Tradit Chinese Med, Shanghai 201203, Peoples R China.
(8.0+极速模式)