COAP‐Palladium‐Catalyzed Asymmetric Linear Allylic Alkylation of Vinyl Benzoxazinanones for Multifunctional 3,3′‐Disubstituted Oxindole Derivatives
Junhao Shen, Sheng‐Suo Zhou, Bailin Wang, Wenkai Liu, Zheng Wang, Xing‐Wang Wang
Abstract
Abstract A Pd‐catalyzed enantioselective linear‐allylic alkylation of vinyl benzoxazinanones with a series of 3‐substituted oxindoles was reported in the presence of a chiral oxamide‐phosphine ligand (COAP−Bn) under mild reaction conditions. A series of optically active multifunctional 3,3′‐disubstituted oxindole derivatives bearing a quaternary stereogenic center and a linear aryl amino side chain were respectively obtained in 55–98% yields with 96–99% ee for 3‐(hetero)aryl substituted oxindoles. The developed protocol demonstrates that the COAP ligands could serve as a privileged chiral ligand to construct diverse chiral 3,3‐disubstituted oxindole compounds with various quaternary stereogenic centers, such as aza ‐, thio ‐ or all‐carbon quaternary stereogenic centers. The salient features of the method include broad substrate scope, N ‐protecting group free, base‐free, and high regio‐ and enantioselectivity. magnified image