Design of Cobalt Phthalocyanine‐Based Covalent Organic Polymers for Accelerated Proton Transfer Hydrogenation

A series of cobalt phthalocyanine‐based covalent organic polymers (COPs) was designed and synthesized for the catalytic hydrogenation of nitroarenes. Notably, the hydrazine‐linked COP demonstrated significantly enhanced catalytic performance, which was 4.76 times and 2.70 times higher than those of the COPs utilizing alkyne and hydroxylamine linkers, respectively. Furthermore, this material exhibits greater structural diversity and superior hydrogenation efficiency compared to conventional cobalt‐based single‐atom catalysts. Density functional theory (DFT) calculations revealed that the hydrazine linkage facilitates a decrease in the hydrogen dissociation energy. Kinetic isotope effect (KIE) studies further confirmed that the proton transfer efficiency is enhanced by 1.3 times and 1.26 times compared to the other two linkers, respectively. This catalyst exhibits superior activity, excellent selectivity (>99%), and remarkable stability (over 10 cycles) in the hydrogenation of diverse nitroarenes under industrially viable conditions.