Über substituierte Pentaphenyl-cyclopentadienyl-Verbindungen und Tetracyclone, XII1 Polarographische und EPR-spektroskopische Untersuchungen zur Konformation von Tetracyclonen und deren Radikalionen / Substituted Pentaphenylcyclopentadienyls and Tetraphenylcyclopentadienones, XII1 The Conformation of Tetraphenylcyclopentadienones and their Anion Radicals as Studied by Polarography and EPR Spectroscopy

Abstract

The polarographic reduction of tetraarylcyclopentadienones is studied in connection with quantummechanical calculations basing on the well known structure of the corresponding ketyls. A linear free energy relationship is found assuming a change in conformation between the redox components. Comparison of the ketone geometry with the conformation of tetraarylpyrryls gives a prove for this surprising result.