Benzotrithiophene-based sp2 carbon-conjugated microporous polymers for green light-triggered oxidation of amines to imines

To optimize the activity at the molecular level, conjugated microporous polymers (CMPs) can be tailored through monomers for visible light photocatalysis . Benzotrithiophene (BTT) is the select monomer for CMPs because of its planar and electron-rich properties. Notably, the sp 2 -carbon conjugation of BTT is highly desirable to facilitate electron transfer . Herein, the condensation of 1,4-phenylenediacetonitrile and 4,4′-biphenyldiacetonitrile with benzo[1,2-b:3,4-b':5,6-b'']trithiophene-2,5,8-tricarbaldehyde assembles two CMPs, sp 2 c-BTT-CMP-1 and sp 2 c-BTT-CMP-2, respectively. Systematic materials characterizations and density functional theory calculations on sp 2 c-BTT-CMP-1 and sp 2 c-BTT-CMP-2 are performed to interpret the essential optoelectronic attributes. Due to the different linkages and π-conjugations, sp 2 c-BTT-CMP-2 presents a better built-in electric field than sp 2 c-BTT-CMP-1, edging toward facile dissociation and fast transport of charge carriers. Consequently, sp 2 c-BTT-CMP-2 is superior to sp 2 c-BTT-CMP-1 for the green light-triggered oxidation of amines to imines with dioxygen. This study underlines the promising aspect of BTT-based CMPs with a fitting linkage as state-of-the-art functional materials for semiconductor photocatalysis.