Bicyclo[6.3.0]undecapentaenyl Anion: The Next Higher Homolog of the Indenyl Anion with Exceptionally Large Ion-Pairing Effects on its Tropicity
作者:Hiroaki Ozoe、Yasutaka Uno、Chitoshi Kitamura、Hiroyuki Kurata、Masaji Oda、John W. Jones、Lawrence T. Scott、Takeshi Kawase
DOI:10.1002/asia.201301307
日期:2014.3
fused to a fully unsaturated eight‐membered ring. A theoretical calculation predicts that the 10‐position of 1 should have the highest electron density. In agreement with this prediction, the reactions of 1 with electrophiles occur predominantly at the 10‐position. The corresponding ferrocene, two fulvenes, two diazo derivatives, and a COT‐fused azulene were obtained by the reactions of 1 with appropriate
标题阴离子1是在几种碱(氢化钠,氢化钾,二异丙基氨基化锂和六甲基二硅叠氮化锂)的作用下,在四氢呋喃(THF)和二甲基亚砜(DMSO)中以相当热稳定的形式生成的[6.3.0]十一碳烯。变温1的1 H NMR光谱1⋅栗+在[d 8 ] THF揭示,阴离子显示出异常大的离子配对效应; 质子化学位移随离子对条件的变化而变化超过1 ppm。因此,接触离子对中的阴离子1(Li +在THF中处于室温下),表现为芳族环戊二烯基阴离子,仅受顺磁性环辛酸酯(COT)的电子作用轻微扰动,而在分离的离子对中为1个(Li +在THF中处于低温或在室温下处于室温) DMSO)表现为具有12个π电子外围的整体亚热带物种。13 C NMR光谱表明没有主要的骨架重排,并且电子密度只有很小的变化。可变性1可以归因于分子的小构象变化。除了其异常的可调性外,阴离子1也可以用作合成与全不饱和八元环稠合的环戊烷共轭体系的通用构件。理