Lewis Acid Catalyzed Intramolecular Direct Ene Reaction of Indoles

How to fuse heterocycles: The direct enamine–imine isomerization of indoles and subsequent intramolecular imino-ene has been observed under Lewis acid catalysis. This unique reaction occurred for indoles that contain a tethered olefin functionality, and led to fused indoline heterocycles with excellent diastereocontrol (see scheme). 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.