Stable Vicinal Bisketene Equivalents for Aryne Diels–Alder Reactions

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.

Keywords

Diels–Alder - Cycloaddition - Annulation - Thiophene - Aryne - Benzyne - Anthraquinone

Publication History

Received: 17 November 2025

Accepted after revision: 10 December 2025

Article published online:
15 January 2026

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