Tandem Brønsted Acid Promoted and Nazarov Carbocyclizations of Enyne Acetals to Hydroazulenones

Abstract

Ring the changes: Enyne acetals were easily converted into hydroazulene skeletons by a new and efficient metal-free route involving a Brønsted acid promoted carbocyclization and a subsequent stereospecific Nazarov cyclization (see scheme). The versatility of this transformation also allowed assembly of interesting heteroaromatic tricyclic systems. 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.