Facile Synthesis of Porphyrin Based Covalent Organic Frameworks via an A 2 B 2 Monomer for Highly Efficient Heterogeneous Catalysis

A new porphyrin covalent organic framework (A 2 B 2 -Por-COF) was readily constructed via self-polycondensation of an A 2 B 2 porphyrin monomer. In contrast to the previously reported porphyrin COFs prepared by co-condensation method, this A 2 B 2 monomer (i.e., two-in-one) strategy provides identically equal stoichiometry of the two different functional groups, and highly crystalline COFs can be obtained much more easily without exhaustive screening of synthetic conditions as used before. Furthermore, comprehensive studies indicated that the A 2 B 2 -Por-COF served as efficient heterogeneous catalysts for selective oxidation of sulfides (up to 98% conversion efficiency and selectivity of >99%) and Knoevenagel condensation (>99% conversion) with excellent stability and recyclability.