Control of the Regio‐ and Stereoselectivity in Diels–Alder Reactions with Quinone Boronic Acids

It all adds up: The dienophilic reactivity of 2-methyl-substituted quinones has been substantially increased by the introduction of a boronic acid substituent, which makes them equivalent to a highly reactive quinone. The Diels–Alder reactions of these quinones are followed by spontaneous and stereoselective protodeboronation to give the trans-fused adducts. The boron group is a temporal regiocontroller and leads to the uncommon meta adduct.