CO₂ Photoactivation Study of Adenine Nucleobase: Role of Hydrogen-Bonding Traction

The discovery and in-depth study of non-biocatalytic applications of active biomolecules are essential for the development of biomimicry. Here, the effect of intermolecular hydrogen-bonding traction on the CO₂ photoactivation performance of adenine nucleobase by means of an adenine-containing model system (AMOF-1-4) is uncovered. Remarkably, the hydrogen-bonding schemes around adenines are regularly altered with the increase in the alkyl (methyl, ethyl, isopropyl, and tert-butyl) electron-donating capacity of the coordinated aliphatic carboxylic acids, and thus, lead to a stepwise improvement in CO₂ photoreduction activity. Density functional theory calculations demonstrate that strong intermolecular hydrogen-bonding traction surrounding adenine can obviously increase the adenine-CO₂ interaction energy and, therefore, result in a smoother CO₂ activation process. Significantly, this work also provides new inspiration for expanding the application of adenine to more small-molecule catalytic reactions.