Retro-Diels–Alder decomposition of norbornadiene mediated by a cationic magnesium complex

Abstract

First evidence for the coordination of norbornadiene (nbd) and dicyclopentadiene (dcpd) with the main group metal Mg is provided by the crystal structures of adducts with cationic β-diketiminate (BDI) Mg complexes. While the dcpd complex is thermally stable, [(BDI)Mg⁺·nbd][B(C₆F₅)₄⁻] shows slow room temperature retro-Diels–Alder decomposition to give a complex with the cation (BDI)Mg(C₅H₅)Mg(BDI)⁺.