Modulation by Amino Acids: Toward Superior Control in the Synthesis of Zirconium Metal–Organic Frameworks

Abstract The synthesis of zirconium metal–organic frameworks (Zr MOFs) modulated by various amino acids, including l ‐proline, glycine, and l ‐phenylalanine, is shown to be a straightforward approach toward functional‐group incorporation and particle‐size control. High yields in Zr‐MOF synthesis are achieved by employing 5 equivalents of the modulator at 120 °C. At lower temperatures, the method provides a series of Zr MOFs with increased particle size, including many suitable for single‐crystal X‐ray diffraction studies. Furthermore, amino acid modulators can be incorporated at defect sites in Zr MOFs with an amino acid/ligand ratio of up to 1:1, depending on the ligand structure and reaction conditions. The MOFs obtained through amino acid modulation exhibit an improved CO 2 ‐capture capacity relative to nonfunctionalized materials.