Iminium–Allenamine Cascade Catalysis: One‐Pot Access to Chiral 4H‐Chromenes by a Highly Enantioselective Michael–Michael Sequence

Taking the Michael-Michael: A cascade Michael–Michael reaction of aryl or alkyl alkynals, involving an unprecedented iminium–allenamine sequence, is efficiently catalyzed by a chiral diphenylprolinol TBDMS ether, and affords highly functionalized 4H-chromenes in high yields. TBDMS=tert-butyldimethylsilyl. 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.