Cascade Pericyclic Reactions of Alleno-Acetylenes: Facile Access to Highly Substituted Cyclobutene, Dendralene, Pentalene, and Indene Skeletons

摘要

Fine tuning of cascade reaction pathways: The allene core of 1,3-di-tert-butyl-1,3-diethynylallenes has been shown in the past to be essentially unreactive. However, its inherent reactivity could be unleashed by the introduction of tailored substituents to induce a variety of highly selective reaction cascades (e.g. 4π electrocyclization, see scheme). These novel processes provide rapid access to densely functionalized carbon skeletons of high molecular complexity in one-pot operations.