Controlled Synthesis of Macrocyclic Carbazole Series with Open-Shell Polycations and Strong NIR-II-Absorbing Chiroptical Responses

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.