Photoinduced concerted multiple-bond rotation has been proposed in some biological systems. However, the observation of such phenomena in synthetic systems, in other words, the synthesis of molecules that undergo photoinduced multiple-bond rotation upon photoirradiation, has been a challenge in the photochemistry field. Here we describe a chalcogen-substituted benzamide system that exhibits photoinduced dual bond rotation in heteroatom-containing bonds. Introduction of the chalcogen substituent into a sterically hindered benzamide system provides sufficient kinetic stability and photosensitivity to enable the photoinduced concerted rotation. The presence of two different substituents on the phenyl ring in the thioamide derivative enables the generation of a pair of enantiomers and E/Z isomers. Using these four stereoisomers as indicators of which bonds are rotated, we monitor the photoinduced C–N/C–C concerted bond rotation in the thioamide derivative depending on external stimuli such as temperature and photoirradiation. Theoretical calculations provide insight on the mechanism of this selective photoinduced C–N/C–C concerted rotation.

在一些生物系统中已经提出了光诱导的协同多键旋转。然而，在合成系统中观察这种现象，换句话说，在光照射下进行光诱导多键旋转的分子的合成，一直是光化学领域的一个挑战。在这里，我们描述了一种硫属取代的苯甲酰胺系统，该系统在含杂原子的键中表现出光致双键旋转。将硫属取代基引入空间位阻苯甲酰胺体系提供了足够的动力学稳定性和光敏性，以实现光诱导的协同旋转。硫代酰胺衍生物中苯环上存在两个不同的取代基，能够生成一对对映体和E / Z异构体。使用这四种立体异构体作为键旋转的指示剂，我们监测硫代酰胺衍生物中光诱导的 C-N/C-C 协同键旋转，具体取决于温度和光照射等外部刺激。理论计算提供了对这种选择性光诱导 C-N/C-C 协同旋转机制的见解。