Perhydroazulenes are common structural motifs in various terpene natural products. Herein, we present the synthesis of parent cis- and trans-perhydroazulenes. Conformational analysis performed with density functional theory (DFT, e.g., B3LYP, M06-2X) and MP2 geometry optimizations with a cc-pVTZ basis set followed by CCSD(T)/cc-pVTZ single point energy computations reveal that the cis-isomer is 0.7
在各种萜烯
天然产物中,全氢氮杂
环丁烷是常见的结构基序。在这里,我们提出了母体顺式和反式过氢azulenes的合成。用密度泛函理论(例如DFT,例如B3LYP,M06-2X)进行构象分析,并使用cc-pVTZ基集进行MP2几何优化,然后进行CC
SD(T)/ cc-pVTZ单点能量计算,揭示了顺式异构体为0.7 kcal mol-1比反式异构体更稳定。1t中存在的立体应变和扭转应变是这种意外的相对顺/反稳定性的原因。