Synthesis of a Polycyclic π-Conjugated System Containing an Azulene Unit by the Flash Vacuum Pyrolytic Method. II. Synthesis and Paratropic Properties of 3<i>H</i>-Cyclopent[<i>a</i>]azulen-3-one and Its Methyl Derivatives
作者:Yoichiro Kitamori、Masafumi Yasunami、Takanori Hioki、Ikue Kikuchi、Kahei Takase
DOI:10.1246/bcsj.65.2131
日期:1992.8
3H-Cyclopent[a]azulen-3-one and two methyl derivalives, which have a new tricyclic π-conjugated system, were synthesized starting from 9-methoxycarbonyl-1,2-dihydro-3H-cyclopent[a]azulen-3-one by the application of flash vacuum pyrolysis in the final step. All proton signals of these compounds were observed at higher fields than those of the referenced 1,2-dihydro compound, but there are no significant
以9-甲氧基羰基-1,2-二氢-3H-环戊[a]azulen-3-为原料合成了具有新三环π-共轭体系的3H-Cyclopent[a]azulen-3-one和2甲基衍生物一种方法是在最后一步应用闪蒸真空热解。在比参考 1,2-二氢化合物更高的场中观察到这些化合物的所有质子信号,但 3H-环戊[a]azulen-3-ones 和参考化合物的碳磁共振之间没有显着差异. 1H NMR 上的这些高场位移在由该分子外围的 12-π 电子系统的贡献引起的感应顺磁环电流方面受到赞赏。3H-cyclopent[a]azulen-3-one在结晶状态下是稳定的,但在溶液中通过脱羰二聚作用逐渐变成六环化合物,而 2-甲基衍生物在结晶态和溶液中都非常稳定。尽管 3H-cyclopent[a]azulen-3-one 与 cyclope...