Functional Groups at Concave Sites: Asymmetric Diels‐Alder Synthesis with Almost Complete (Lewis‐Acid Catalyzed) or High (Uncatalyzed) Stereoselectivity

A new concept for development of reagents for asymmetric syntheses was used as a basis for the synthesis of alcohols (1) and (2). Their fumarates undergo Lewis-acid catalyzed or uncatalyzed addition to anthracene with very good stereo-selectivity; depending on whether a derivative of (1) or (2) is the educt, inverse configurated products are obtained.