Lavarda Giulia, Bhattacharjee Nicholus, Brancato Giuseppe, Torres Tomás, Bottari Giovanni
Departamento de Química Orgánica, Universidad Autónoma de Madrid, Campus de Cantoblanco, 28049, Madrid, Spain.
Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126, Pisa, Italy.
Angew Chem Int Ed Engl. 2020 Nov 16;59(47):21224-21229. doi: 10.1002/anie.202010133. Epub 2020 Sep 11.
In recent years, several tetracyanobuta-1,3-diene (TCBD) conjugates have been prepared by linking the tetracyano unit to various electroactive moieties. These push-pull conjugates, besides showing interesting physicochemical properties, are axially chiral, a feature arising from the restricted rotation around the central bond of the butadiene. Yet, only in a few cases, separation and isolation of the enantiomers have been successfully achieved, owing to the configurational lability of the corresponding enantiopure species. Herein, we report the first example of photo- and electroactive TCBD-based derivatives showing unprecedented configurational stability and a peculiar light-triggered enantiomer conversion mechanism enabled by triple-state photogeneration. These systems represent a nice addition to the fast-increasing arsenal of artificial, light-controllable molecular switches.
近年来，通过将四氰基单元与各种电活性部分相连，制备了几种四氰基丁-1,3-二烯（TCBD）共轭物。这些推拉共轭物除了表现出有趣的物理化学性质外，还是轴向手性的，这一特征源于围绕丁二烯中心键的受限旋转。然而，由于相应对映体纯物种的构型不稳定性，仅在少数情况下成功实现了对映体的分离和分离。在此，我们报道了首例基于TCBD的光活性和电活性衍生物，其表现出前所未有的构型稳定性以及由三重态光生引发的独特光触发对映体转化机制。这些系统是快速增加的人工光控分子开关库中的一个很好补充。
