Sankararaman Sethuraman, Venkataramana Gandikota, Varghese Babu
Department of Chemistry, Sophisticated Analytical Instrument Facility, Indian Institute of Technology Madras, Chennai 600036, India.
J Org Chem. 2008 Mar 21;73(6):2404-7. doi: 10.1021/jo7024724. Epub 2008 Feb 16.
The first example of isolation and X-ray crystallographic structural characterization of two conformers arising from rotation along a diacetylenic bond is reported. In both the conformers extensive pi-pi interactions are observed in the solid state. VT-NMR and fluorescence spectroscopic studies in solution suggest that the closed and open conformers are in equilibrium and that the closed conformer is the predominant species at room temperature.
报道了沿二乙炔键旋转产生的两种构象异构体的分离及X射线晶体学结构表征的首个实例。在两种构象异构体中，固态下均观察到广泛的π-π相互作用。溶液中的变温核磁共振（VT-NMR）和荧光光谱研究表明，封闭和开放构象异构体处于平衡状态，且封闭构象异构体在室温下是主要物种。
