Nickel‐Catalyzed, Directing‐Group‐Assisted [2+2+2] Cycloaddition of Imine and Alkynes

Abstract

An aldimine bearing a 3-methyl-2-pyridyl group undergoes [2+2+2] cycloaddition reaction with two alkyne molecules under nickel catalysis to afford a 1,2-dihydropyridine derivative in moderate to good yield. The reaction is likely to involve oxidative cyclization of the imine and alkyne, insertion of another alkyne, and CN reductive elimination, followed by a 1,5-sigmatropic hydrogen shift. The pyridyl group is proposed to facilitate the reaction by chelation to the aza-nickelacycle intermediates. Detailed facts of importance to specialist readers are published as ”Supporting Information”. Such documents are peer-reviewed, but not copy-edited or typeset. They are made available as submitted by the authors. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.