Annulated pyridines are ubiquitous scaffolds in many bioactive molecules. A highly regio-and enantioselective Ni(0)-catalyzed endo-selective C−H cyclization of pyridines with alkenes has been developed. An unprecedented enantioselective C−H activation at pyridyl 3-or 4-positions was enabled by bulky chiral Nheterocyclic carbene ligands. This protocol provides expedient access to a series of optically active 5,6,7,8tetrahydroquinolines and 5,6,7,8-tetrahydroisoquinolines, compounds otherwise accessed with difficulty, in moderate to high yields (up to 99% yield) and enantioselectivities (up to 99% ee). To our knowledge, this is the first example of enantioselective C−H cyclization of pyridines to chiral annulated products.

Reported is a highly enantioselective Ni(0)‐catalyzed endo‐selective C−H annulation of 2‐ and 4‐pyridone, and 4‐pyrimidone with alkenes to provide drug‐relevant bicyclic heterocycle products. The use of a readily prepared chiral bulky NHC ligand (SIPE) for Ni catalyst and commercially available AlEt3 as co‐catalyst enhanced the practicality of this reaction.

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