Generating Skeletal Diversity and Complexity from Boron‐Substituted 1,3‐Dienes and Enophiles

Boron‐substituted 1,3‐dienes participate in ene reactions to afford new functionalized synthetic intermediates. After evaluating several enophiles as partners, the resulting products have been engaged in multistep sequences involving first a Diels Alder/allylboration process. A variety of skeletally diverse and complex polycyclic heterocycles were thus synthesized, such as tetrahydro‐1H‐isoindole‐1,3(2H)‐diones, eight‐membered lactones or tricyclic spiro compounds. Ene reactions of boron‐substituted 1,3‐dienes afford new functionalized privileged precursors of skeletally diverse and complex polycyclic heterocycles. Multistep sequences based on a key Diels Alder/allyboration process are thus used to access tetrahydro‐1H‐isoindole‐1,3(2H)‐diones, eight‐membered lactones or tricyclic spiro compounds.