Ligand-tuned cobalt-containing coordination polymers and applications in water

Abstract

Ligands play a key role in modern catalysis research and occasionally determine whether a reaction will take place under specific conditions, such as in water. In this experiment, ligands containing an indole-based diacid moiety were employed to prepare the corresponding cobalt coordination polymer material (Co-CIA) and porous oval polymer material (Co-NCIA). Interestingly, it was observed that Co-CIA could promote the alkylation of ketones with alcohols and alcohols with alcohols, while Co-NCIA was effective for the synthesis of 1-benzyl-2-aryl-1H-benzo[d]imidazoles from various phenylenediamine and benzyl alcohols through borrowing hydrogen and dehydrogenation strategies. Other mechanism explorations, such as deuterium labeling experiments and a kinetics study, were conducted to better understand Co-CIA and Co-NCIA systems and the related transformations. Our studies provided an efficient method for the development of highly active cobalt coordination polymer materials with excellent recovery performance for dehydrogenation and borrowing hydrogen reactions under water and base-free conditions.