A General Approach to Optically Pure [5]‐, [6]‐, and [7]Heterohelicenes

Abstract

Spiral staircases: A general method for the preparation of optically pure [5]-, [6]-, and [7]heterohelicenes is based on a CoI- or Ni0-catalyzed diastereoselective [2+2+2] cycloisomerization of centrally chiral triynes to deliver helicenes comprising two 2H-pyran rings. The configuration, which can be predicted, does not depend on helicene length or functional groups present. 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.