η⁶‐(1,2‐Dioxocyclobutabenzene)tricarbonyl‐chromium(0): Starting Material for Double Anionic Oxy‐Cope Rearrangements under Very Mild Conditions

Abstract

Certainly one of the most strained arene complexes known, the title compound 1 is described here. Its reactivity is characterized by the differentiation of the sides of attack at the bicyclic ligand. On addition of alkenyl metal reagents this leads to an ideal configuration for double anionic oxy-Cope rearrangements, providing access to benzoannelated cyclooctan-1,4-dione derivatives.