π-conjugated chiral macrocycles show fascinating structures and are of interest in synthetic chemistry and material science.Herein,we describe a new series of electron-rich macrocycles that are composed of all-carbaz...π-conjugated chiral macrocycles show fascinating structures and are of interest in synthetic chemistry and material science.Herein,we describe a new series of electron-rich macrocycles that are composed of all-carbazole moieties which can promise the robust structure-dependent redox chemistry.Controlled synthesis of the nearly planar MC[4]was selectively obtained either by a[3+1]or[2+2]coupling reaction of carbazole units.In contrast,stitching of the carbazole trimers via the tetrafunctional bicarbazole linkers gave rise to the rarely accessible biscyclic systems,such as BMC[4]and the chiral C-BMC[4]with a unique figure-eight conformation.The electron-rich nature in their neutral states enables a facile transformation under chemical and electrochemical conditions to the positively charged polycationic states with multispin open-shell characters.Interestingly,the tetracation MC[4]^(4+)is predicted to exhibit global aromaticity due to charge delocalization,and the CD spectra of chiral species C-BMC[4]^(4+4•)are shifted far into the NIR-II up to∼2200 nm.This work provides a fundamental step toward the novel synthesis of electron-rich chiral macrocycles followed by highly charged polycyclophanes with potential applications in chirospintronics and NIR-active optoelectronic materials.展开更多
基金financially supported by National Natural Science Foundation of China(grant nos.22471014,22271013,and 21772012)Beijing Natural Science Foundation(grant no.2232024).
文摘π-conjugated chiral macrocycles show fascinating structures and are of interest in synthetic chemistry and material science.Herein,we describe a new series of electron-rich macrocycles that are composed of all-carbazole moieties which can promise the robust structure-dependent redox chemistry.Controlled synthesis of the nearly planar MC[4]was selectively obtained either by a[3+1]or[2+2]coupling reaction of carbazole units.In contrast,stitching of the carbazole trimers via the tetrafunctional bicarbazole linkers gave rise to the rarely accessible biscyclic systems,such as BMC[4]and the chiral C-BMC[4]with a unique figure-eight conformation.The electron-rich nature in their neutral states enables a facile transformation under chemical and electrochemical conditions to the positively charged polycationic states with multispin open-shell characters.Interestingly,the tetracation MC[4]^(4+)is predicted to exhibit global aromaticity due to charge delocalization,and the CD spectra of chiral species C-BMC[4]^(4+4•)are shifted far into the NIR-II up to∼2200 nm.This work provides a fundamental step toward the novel synthesis of electron-rich chiral macrocycles followed by highly charged polycyclophanes with potential applications in chirospintronics and NIR-active optoelectronic materials.
