Wang Mengjie, Dang Lanping, Xu Wan, Ma Zhiying, Shao Liuliu, Wang Guangxia, Li Chunli, Wang Hua
Engineering Research Center for Nanomaterials, Henan University, Kaifeng, 475004, China.
Beilstein J Org Chem. 2022 Jul 8;18:809-817. doi: 10.3762/bjoc.18.81. eCollection 2022.
2,5-Di(trimethylsilanyl)dithieno[2,3-:3',2'-]thiophene ((TMS)--), 2,5-di(trimethylsilanyl)diseleno[2,3-:3',2'-]thiophene ((TMS)--), and 2,5-di(trimethylsilanyl)diseleno[2,3-:3',2'-] selenophene ((TMS)--) were used as starting materials to synthesize three S-shaped double helicenes (i.e., -, -, and -) through monobromination, formylation, the Wittig reaction, and double oxidative photocyclization. The photocyclization was a highly regioselective process. The molecular structures of - and - were confirmed by X-ray single-crystal analysis. Multiple intermolecular interactions, such as C-S, C-Se, S-S, S-Se, and Se-Se, were observed in the crystal packing structures of these compounds. Spectroscopic results and our previous work showed that the combination of molecular structure change and heteroatom replacement from S to Se could precisely modulate molecular energy levels.
2,5-二（三甲基硅烷基）二噻吩并[2,3-:3',2'-]噻吩（（TMS）--）、2,5-二（三甲基硅烷基）二硒吩并[2,3-:3',2'-]噻吩（（TMS）--）和2,5-二（三甲基硅烷基）二硒吩并[2,3-:3',2'-]硒吩（（TMS）--）被用作起始原料，通过单溴化、甲酰化、维蒂希反应和双氧化光环化反应合成了三种S形双螺旋烯（即-、-和-）。光环化是一个高度区域选择性的过程。-和-的分子结构通过X射线单晶分析得到证实。在这些化合物的晶体堆积结构中观察到了多种分子间相互作用，如C-S、C-Se、S-S、S-Se和Se-Se。光谱结果和我们之前的工作表明，分子结构变化和从S到Se的杂原子取代的结合可以精确调节分子能级。
