Rotational Isomerism in Fluorene Derivatives. III. The Conformation of 9-(9-Fluorenyl)-9-(2-substituted 9-fluorenyl)fluorene Derivatives
作者:Shoji Kajigaeshi、Shizuo Fujisaki、Ichishi Aizu、Hiroshi Hara
DOI:10.1246/bcsj.52.3569
日期:1979.12
The conformations of 9,9-di(9-fluorenyl)fluorene derivatives (1) with substituents at the 2- or 2,7-positions in a terminal fluorene ring were illustrated by the gauche-gauche forms at room temperature. DNMR studies of 1 gave the values of about 85–88 kJ/mol for the free energy of activation (ΔG\eweq) for the restricted rotation around the C(9)–C(9) bonds. The conformation of 9,9-di(9-fluorenyl) fluorene
9,9-二(9-芴基)芴衍生物 (1) 在末端芴环的 2- 或 2,7- 位具有取代基的构象在室温下由 gauche-gauche 形式说明。1 的 DNMR 研究给出了围绕 C(9)-C(9) 键的受限旋转的活化自由能 (ΔG\eweq) 的值约为 85-88 kJ/mol。1 的母体化合物 9,9-二(9-芴基) 芴的构象也显示为室温下唯一的 gauche-gauche (+sc, +sc 或 -sc, -sc) 形式。