The reactions of o-benzoquinones with cyclopentadiene

Abstract

Diels–Alder reactions between a number of alkyl-, aryl-, alkoxy-, and chloro-substituted o-benzoquinones and cyclopentadiene are reported. The ability of the quinone to react both as a diene and dienophile is illustrated, and the reaction products have been analysed spectroscopically. The intercoversion of the two types of product by way of a Cope rearrangement it discussed and the rearrangement is shown to be intramolecular.