Stereochemistry of Polyethylated Aromatic Systems

Hexaethylbenzene adopts a conformation with the ethyl groups perpendicular to the aromatic ring and oriented in a fully alternated up-down arrangement. The synthesis, stereochemistry and rotational barriers of systems possessing two polyethylaryl rings in spatial proximity (e.g., decaethylbiphenyl, octaethylbiphenylene) are reviewed. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)