2‑Substituted 1,4-Naphthoquinones in [6 + 4]-Cycloaddition with 8,8-Dicyanoheptafulvene

This study demonstrates
that classical lowest unoccupied molecular
orbital reactivity of 2-substituted 1,4-naphthoquinones is possible
to be reversed by deprotonation and application of the resulting dienolate
as a 4π component in the higher-order [6 + 4]-cycloaddition
proceeding in a completely pericyclic manner. 8,8-Dicyanoheptafulvene
was shown to be an efficient 6π component in the developed reaction
opening the access to functionalized cycloadducts in a diastereoselective
manner by employing organocatalytic activation. Attempts to introduce
enantioselective version of the developed higher-order cycloaddition
were also undertaken.