Controllable multiple-step configuration transformations in a thermal/photoinduced reaction

Meng-Fan Wang  , Yan Mi , Fei-Long Hu , Hajime Hirao , Zheng Niu , Pierre Braunstein & Jian-Ping Lang

Solid-state photochemical reactions of olefinic compounds have been demonstrated to represent powerful access to organic cyclic molecules with specific configurations. However, the precise control of the stereochemistry in these reactions remains challenging owing to complex and fleeting configuration transformations. Herein, we report a unique approach to control the regiospecific configurations of C = C groups and the intermediates by varying temperatures in multiple-step thermal/photoinduced reactions, thus successfully realizing reversible ring closing/opening changes using a single-crystal coordination polymer platform. All stereochemical transitions are observed by in situ single-crystal X-ray diffraction, powder X-ray diffraction and infrared spectroscopy. Density functional theory calculations allow us to rationalize the mechanism of the synergistic thermal/photoinduced transformations. This approach can be generalized to the analysis of the possible configuration transformations of functional groups and intermediates and unravel the detailed mechanism for any inorganic, organic and macromolecular reactions susceptible to incorporation into single-crystal coordination polymer platforms

热/光诱导反应中可控的多步构型转换

已证明烯烃化合物的固态光化学反应代表了对具有特定构型的有机环状分子的强大访问。然而，由于复杂且短暂的构型转变，这些反应中立体化学的精确控制仍然具有挑战性。在这里，我们报告了一种独特的方法，通过在多步热/光诱导反应中改变温度来控制 C = C 基团和中间体的区域特异性构型，从而使用单晶配位聚合物平台成功实现可逆的闭环/开环变化。通过原位单晶 X 射线衍射、粉末 X 射线衍射和红外光谱观察到所有立体化学转变。密度泛函理论计算使我们能够合理化协同热/光诱导转变的机制。这种方法可以推广到分析官能团和中间体的可能构型转变，并揭示任何易于掺入单晶配位聚合物平台的无机、有机和大分子反应的详细机制。

DOI: 10.1038/s41467-022-30597-w