Hyperstable alkenes: are they remarkably unreactive?

Abstract

In 1981, Maier and Schleyer first identified a select number of cage bicyclic olefins (alkenes) as “hyperstable”, and predicted them to be “remarkably unreactive”, based solely on theoretical methods. Since that time only three ad hoc systems meeting the criteria of a hyperstable alkene have been reported in the literature. A one-pot, telescoped synthesis, of four hyperstable alkenes is reported herein, which has uncovered unexpected reactivity towards oxidation. Although, this work represents a new benchmark in hyperstable alkenes, it concomitantly emphasised the need to clarify the definition based on a long-held computational prediction.