Highly Specific Coordination-Driven Self-Assembly of 2D Heterometallic Metal–Organic Frameworks with Unprecedented Johnson-type (J₅₁) Nonanuclear Zr-Oxocarboxylate Clusters

The quest for new and unique polynuclear metal-oxocarboxylate clusters has led to a continual boom of highly connected and robust metal–organic frameworks (MOFs) with intriguing properties. In this work, by virtue of a highly specific coordination-driven cluster rearrangement process of a presynthesized trinuclear zirconocene-based tripodal metallo-pyridine ligand, we realized the preparation of the first two 2D heterometallic MOFs incorporating unprecedented Johnson-type (J₅₁) nonanuclear Zr-oxocarboxylate clusters, as unambiguously uncovered by single-crystal X-ray crystallography. The resultant two charged frameworks feature counteranion-dependent 3,6-c kgd (JMOF-1) and 3,12-c 3,12L4 (JMOF-2) nets that are formed by octahedral and hexagonal prismatic Zr₉ molecular building blocks (MBBs), respectively. In addition, JMOF-2 shows promise for the purification of acetylene from CO₂ and C₂H₄, with IAST selectivities of about 12 and 8, respectively, at 298 K and 1 bar, as well as remarkable iodine capture capacity of up to 2.4 g g^–1.