Rearrangement Reactions of Tritylcarbenes: Surprising Ring Expansion and Computational Investigation
作者:Klaus Banert、Manfred Hagedorn、Tom Pester、Nicole Siebert、Cornelius Staude、Ivan Tchernook、Katharina Rathmann、Oldamur Hollóczki、Joachim Friedrich
DOI:10.1002/chem.201501352
日期:2015.10.12
molecular dynamics calculations. From these investigations, the fused bicyclobutane intermediate was found to be essential for heptafulvene formation. Although the bicyclobutane is also capable of rearranging to the triphenylethene product, only the heptafulvene pathway is reasonable from the energetics. The ethene is formed straight from cyanotritylcarbene.
通常,由于通常会形成1,2,3-三唑,因此乙炔化物和磺酰叠氮化物不会进行亲电子叠氮化物转移。我们现在显示,用丁基锂处理三苯乙炔,然后暴露于2,4,6-三异丙基苯磺酰叠氮化物,所产生的产物很容易通过短寿命的三苯乙炔基叠氮化物及其次级产物氰基三甲基卡宾的生成来解释。此外,如文献所述,已证明三苯甲基卡宾通常不仅仅产生三苯乙烯。相反,这些卡宾总是也产生(二苯基亚甲基)环庚烯(庚富烯)作为副产物。静态DFT,偶联簇和从头算分子动力学计算支持了该结果。从这些调查中 发现稠合的双环丁烷中间体对于七氟戊醚的形成是必不可少的。尽管双环丁烷也能够重排成三苯乙烯产物,但从高能学角度来看,只有七富翁途径是合理的。乙烯是直接由氰基三甲基卡宾形成的。