Asymmetric Binary‐Acid Catalysis with InBr3 in the Inverse‐Electron‐Demanding Hetero‐Diels–Alder Reaction of Mono‐ and Bis‐Substituted Cyclopentadienes: Remote Fluoro‐Effect on Stereocontrol

Remote F effect: Unprecedented hetero-Diels–Alder reactions of mono- and bis-substituted cyclopentadienes have been realized by an asymmetric binary-acid catalyst that synergistically combines a chiral phosphoric acid 1 h/InBr3 with good periselectivity, high regioselectivity, and excellent stereoselectivity. Substituent mapping of the chiral phosphoric acid indicates a dramatic remote ortho-fluoro effect on the stereocontrol (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.