Enantioselective Synthesis of 4‐Hydroxytetrahydropyridine Derivatives by Intramolecular Addition of Tertiary Enamides to Aldehydes

Stable tertiary enamides and enecarbamates undergo highly enantioselective intramolecular nucleophilic addition to aldehyde units catalyzed by chiral binol–Ti complexes under mild conditions to produce the title compounds in up to 99.5 % or greater enantiomeric excess. A positive nonlinear effect was detected and the formation of binol–Ti aggregates suggests an intricate asymmetric catalytic pathway. 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.