Porphyrin based covalent organic frameworks via self-polycondensation for heterogeneous photocatalysis

A novel porphyrin based covalent organic frameworks (Por-BABN-COF) has been successfully constructed via self-polycondensation of a newly developed A₂B₂ porphyrin building block possessing two amino groups and two neopentyl acetal at the meso-position. Por-BABN-COF was employed as a heterogeneous photocatalyst for the selective oxidation of sulfides and CO₂ cycloaddition due to its superior light absorption capacity, strong crystallinity and high stability. The high conversion, good selectivity and excellent reusability indicate Por-BABN-COF is a promising photocatalyst for both reactions. Mechanistic investigations confirm that electron transfer pathways contribute to the formation of sulfoxides. This study presents a new strategy for designing and developing high-efficient porphyrin-based COFs as heterogeneous photocatalysts for selective organic transformations.