Enantioselective construction of triaryl-substituted all-carbon quaternary stereocenters via organocatalytic arylation of oxindoles with azonaphthalenes†
Mei-Jun Lv,Jun Kee Cheng,Shao-Hua Xiang,Xiang-Zhong Ren,Junmin Zhang,Bin Tan
Chemical Science Pub Date : 02/06/2023 00:00:00 , DOI:10.1039/D2SC07103G
Abstract

Azonaphthalenes have been verified as a class of effective arylation reagents in a variety of asymmetric transformations. Here a highly efficient approach to construct triaryl-substituted all-carbon quaternary stereocenters through chiral phosphoric acid-catalyzed enantioselective arylation of 3-aryl-2-oxindoles with azonaphthalenes is disclosed. This chemistry is scalable and displays excellent functional group tolerance, furnishing a series of 3,3-disubstituted 2-oxindole derivatives in good yields with excellent enantiocontrol. Preliminary mechanistic data suggest that the initially formed direct addition intermediate undergoes intramolecular annulation under acidic reaction conditions.

Graphical abstract: Enantioselective construction of triaryl-substituted all-carbon quaternary stereocenters via organocatalytic arylation of oxindoles with azonaphthalenes