Shen Bowen, Pan Chunyu, Feng Xiaopeng, Kim Jehan, Sun Mo, Lee Myongsoo
Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Fudan University, Shanghai, 200438, China.
State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, China.
Angew Chem Int Ed Engl. 2023 Apr 24;62(18):e202300658. doi: 10.1002/anie.202300658. Epub 2023 Mar 27.
Although two-dimensional (2D) chiral sheet structures are attractive because of their unique chemical and physical properties, single layer 2D chiral network structures with switchable pore interior remain elusive. Here we report spontaneous chirality induction in a single layer 2D network structure formed from the self-assembly of tetrapod azobenzene molecules. The chirality induction arises from multiple sublayers slipped in a preferred direction in which the sublayer consists of unidentical molecular arrangements in the in-plane a and b directions, breaking both the plane of symmetry and inversion symmetry. The protruded azobenzene units in the pore interior can be selectively isomerized upon UV irradiation, resulting in a reversible deformation of the chiral pores while maintaining the 2D frameworks. The chiral network can thus selectively entrap one enantiomer from a racemic solution with near perfect enantioselectivity, and then release it upon UV irradiation.
尽管二维（2D）手性片层结构因其独特的化学和物理性质而颇具吸引力，但具有可切换孔内结构的单层2D手性网络结构仍然难以实现。在此，我们报道了由四足偶氮苯分子自组装形成的单层2D网络结构中的自发手性诱导。手性诱导源于多个子层在优选方向上的滑移，其中子层在平面内a和b方向上由不相同的分子排列组成，打破了对称平面和反演对称性。孔内突出的偶氮苯单元在紫外线照射下可选择性异构化，导致手性孔发生可逆变形，同时保持2D框架结构。因此，手性网络可以从外消旋溶液中选择性地捕获一种对映体，具有近乎完美的对映选择性，然后在紫外线照射下释放它。
