Reactivity of<i>exo</i>- and<i>endo</i>-Tricyclo[3.2.1.0<sup>2,4</sup>]octan-8-ylidenes and 7-Norbornenylidene
作者:Shun-ichi Murahashi、Kazuo Okumura、Yusuke Maeda、Akio Sonoda、Ichiro Moritani
DOI:10.1246/bcsj.47.2420
日期:1974.10
endo-Tricyclo[3.2.1.02,4]octan-8-ylidene (2) generated by the thermolysis of sodium salt of endo-tricyclo[3.2.1.02,4]octan-8-one tosylhydrazone (5) gave toluene (3.9%), cyclohepta-1,4-diene(6, 14%), cyclohepta-1,3-diene(7, 3.5%), bicyclo[3.3.0]octa-1,6-diene(8, 4.8%), bicyclo[3.3.0]octa-1,7-diene(9, 9.0%), and endo-tricyclo[3.2.1.02,4]octane (10, 21%). In sharp contrast, exo-tricyclo[3.2.1.02,4]oct-8-ylidene
由内三环[3.2.1.02,4]辛烷-8-酮甲苯磺酰腙(5)的钠盐热解生成的内-三环[3.2.1.02,4]辛-8-亚基(2)得到甲苯(3.9%) ), cyclohepta-1,4-diene(6, 14%), cyclohepta-1,3-diene(7, 3.5%), bicyclo[3.3.0]octa-1,6-diene(8, 4.8%),双环[3.3.0]辛烷-1,7-二烯(9, 9.0%)和内三环[3.2.1.02,4]辛烷(10, 21%)。与此形成鲜明对比的是,外型三环 [3.2.1.02,4] oct-8-ylidene (1) 得到甲苯 (1.5%) 和三环 [5.1.01,7]oct-5-ene (14, 57%)。结果表明二价碳的 p 轨道与环丙烷的对称沃尔什轨道之间存在显着的同共轭相互作用。这与 7-降冰片亚基 (3) 的结果一致,其中二价碳和碳碳双键之间的相互作用稳定了非经典亚甲基。