Carbazole–anthraquinone conjugated microporous polymer photocatalysis for aerobic oxidative cyanation of tertiary amines irradiated by green light

[Display omitted] •A carbazole–anthraquinone CMP, namely CzAQ-CMP, is fabricated.•Electron transfer to O2 via anthraquinone of CzAQ-CMP forms O2•– irradiated by green light.•Hole at carbazole of CzAQ-CMP drives aerobic oxidative cyanation of N,N-dimethylaniline with CN− in CH3OH.•The nucleophilic substitution by O2•– releases CN− from TMSCN to partake in the α-cyanation of N,N-dimethylaniline.•The oxidative cyanation of tertiary amines affords the corresponding α-aminonitriles in high yields over CzAQ-CMP. Conjugated microporous polymers (CMPs), which can be designed through molecular building units, have been widely exploited as photoactive materials. Herein, carbazole and anthraquinone are utilized to prepare a carbazole–anthraquinone CMP (CzAQ-CMP) for visible light photocatalysis. Theoretical calculations suggest hole and electron are located at carbazole and anthraquinone, respectively. Besides, CzAQ-CMP allows for electron transfer to molecular oxygen via anthraquinone, forming superoxide. The hole of CzAQ-CMP drives aerobic oxidative cyanation of N,N-dimethylaniline in methanol. Intriguingly, in the presence of acetic acid, the nucleophilic substitution of trimethylsilyl cyanide by superoxide releases cyanide ion to partake in the α-cyanation of N,N-dimethylaniline. Irradiated by green light, the oxidative cyanation of diverse tertiary amines favorably affords the corresponding α-aminonitriles over CzAQ-CMP in high yields. This work illuminates the rational design of CMPs for photocatalytic selective organic transformations.