Synthesis and Oxidative Coupling of Bi-cyclononatetraenylide – Reaction of Bi-cyclononatetraenyl with Potassium

Abstract

Contrary to literature reports, treatment of bi-cyclononatetraenyl (1) with potassium does not give bi-cyclononatetraenylide (2), but ccct -cyclononatetraenide (6) in a high yield. Twofold deprotonation of the ring assembly 1 takes place after equilibration 1 ⇌ 1' followed by treatment of 1' with K-tert-butoxide/Li-diisopropylamide. The structure of 2 follows from its spectroscopic data as well as from the successful oxidative treatment of 2 with Ag^⊕ to give thermally unstable nonafulvalene (3).