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Herein, a cobalt-catalyzed intramolecular enantioselective reductive Heck reaction is disclosed. Starting from N - ortho -iodoaryl-2-(trifluoromethyl)acrylamides, a plethora of chiral oxindoles bearing trifluoromethylated quaternary stereogenic centers at the C3-position are achieved in moderate to good yields (up to 88% yield) and good to excellent enantioselectivities (up to 94% ee) by employing zinc/silane as reducing agent. Other than the trifluoromethyl group, a number of chiral oxindoles bearing alkyl, aryl, and ester groups at C3-position were also obtained albeit in relatively lower enantioselectivities (68-78% ee).

Enantioselective [3 + 2] annulation of N -heteroarenes with alkynes has been developed via a cobalt-catalyzed dearomative umpolung strategy in the presence of chiral ligand and reducing reagent. A variety of electron-deficient N -heteroarenes, including quinolines, isoquinolines, quinoxaline, and pyridines, and internal or terminal alkynes are employed in this reaction, showing a broad substrate scope and good functionality tolerance. Annulation of electron-rich indoles with alkynes is also developed. This protocol provides a straightforward access to a variety of N -spiroheterocyclic molecules in excellent enantioselectivities (76 examples, up to 99% ee).

Arylboration and arylsilylation reactions of N -(2-iodoaryl)acrylamides with bis(pinacolato)-diboron (B 2 pin 2 ) or PhMe 2 Si-Bpin are developed by using simple CuOAc as the sole catalyst. A range of boron- or silane-bearing 3,3'-disubstituted oxindoles are obtained in moderate to excellent yields. The reaction is proposed to proceed via a domino sequence involving intermolecular olefin borylcupration or silylcupration followed by intramolecular coupling of an alkyl-Cu intermediate with aryl iodide.