Competing Diels-Alder Reactions of Activated Nitroethylene Derivatives and [3,3]-Sigmatropic Rearrangements of the Cycloadducts.

Diels–Alder reaction of nitroethylene derivatives with cyclohexa-1,3-diene afforded three pericyclic products some of which could be converted to others via a new [3,3]-sigmatropic rearrangement or via a Claisen rearrangement.