Department of Chemistry and Drug Technologies, Sapienza University of Rome, Piazzale Aldo Moro 5, 00185 Roma, Italy.
Department of Industrial Chemistry "Toso Montanari", University of Bologna, Viale del Risorgimento 4, 40136 Bologna, Italy.
Molecules. 2023 Jun 22;28(13):4915. doi: 10.3390/molecules28134915.
The dynamic scenario of di-aryls-pyrano-chromenes was investigated using DFT calculations. The symmetry of the chromene scaffold and the presence of two -substituted aryls substituents can generate two / diastereoisomers and conformational enantiomers with different rotational barriers. The relative conformations and configurations were derived using NOESY-1D experiments. Depending on the energies related to the conformational exchange, the experimental energy barriers were determined through Dynamic NMR, Dynamic HPLC or kinetic studies. The atropisomeric pairs were resolved in the latter scenario, and their absolute configuration was assigned using the ECD/TD-DFT method.
使用 DFT 计算研究了二芳基吡喃色烯的动态情况。色烯支架的对称性和两个取代的芳基取代基的存在可以生成两种非对映异构体和构象对映异构体，它们具有不同的旋转势垒。通过 NOESY-1D 实验得出相对构象和构型。根据与构象交换相关的能量，通过动态 NMR、动态 HPLC 或动力学研究确定实验能量势垒。在后一种情况下，对阻转异构体对进行了拆分，并使用 ECD/TD-DFT 方法确定了它们的绝对构型。
