Enantioselective Synthesis of Sterically Hindered Tertiary ¿-Aryl Oxindoles via Palladium-Catalyzed Decarboxylative Protonation. An Experimental and Theoretical Mechanistic Investigation

Identificador:  imarina:4123847

Handle: https://hdl.handle.net/20.500.11797/imarina4123847

Autors:  Biosca, Maria; Jackson, Mark; Magre, Marc; Pamies, Oscar; Norrby, Per-Ola; Dieguez, Montserrat; Guiry, Patrick J

Resum:
© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim We have developed the first catalytic asymmetric preparation of sterically hindered tertiary α-aryl oxindoles via enantioselective palladium-catalyzed decarboxylative protonation of the corresponding α-aryl-β-amido allyl esters. The reaction occurs under very mild conditions and in short reaction times, providing excellent yields and promising enantioselectivities (ee's up to 78%). We have also performed an experimental investigation of the reaction mechanism and employed theoretical calculations to understand the nature of the enantioselectivity-determining step. (Figure presented.).