An Approach to Five-Membered Lactams from Aliphatic Amides and Terminal Acetylenes by Nickel Catalysis

A nickel-catalyzed facile synthesis of structurally diverse five-membered lactams from aliphatic amides and terminal acetylenes with the assistance of an 8-aminoquinolyl auxiliary has been achieved. A broad range of terminal acetylenes and aliphatic amides proved to be the efficient coupling partners, furnishing the corresponding lactams in moderate to good yields. The transformation is proven to undergo an oxidative alkynylation followed by the intramolecular annulation process. The methodology can be extended to aromatic amides and acrylamides, which provides an efficient and straightforward protocol for the construction of a variety of isoindolinone and pyrrolidinone derivatives.