Abstract 2,5-Bis(tert-butyldimethylsilyloxy)thiophenes are introduced as bench-stable Diels–Alder dienes for reaction with arynes as dienophiles. Ring opening of the cycloadducts can be achieved via TBAF-promoted desilylation, providing convergent, redox-neutral access to a library of substituted naphthoquinones. Strategically, this two-step sequence represents the application of stable vicinal bisketene equivalents as Diels–Alder dienes. Extension to anthraquinones is also demonstrated, in this case via mild autoxidation of a readily accessible cyclohexenyl-fused derivative.
Budwitz et al. (Thu,) studied this question.