Enol radical cations in solution. Part 12. Synthesis and electrochemical investigations of a stable enol linked to a ferrocene redox centre †

Abstract

The synthesis of the first stable enol linked to a ferrocene redox centre is reported. After one-electron oxidation of this compound we receive a persistent radical cation that can be activated by a second one-electron oxidation step. The resulting enol dication undergoes rapid deprotonation to a diradical cation which finally furnishes two benzofurans as products. The mechanism of this reaction and the role of the ferrocene as a redox relay is discussed.

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