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Updated: Jul 7, 2026
Synthesis of Triazole and Tetrazole-Functionalized Zr-Based Metal-Organic Frameworks Through Post-Synthetic Ligand Exchange
Published on: June 23, 2023
Tetranuclear CoII, MnII, and CuII complexes of a novel binucleating pyrazolate ligand preorganized for the
Jarl Ivar van der Vlugt1, Serhiy Demeshko, Sebastian Dechert
1Institut für Anorganische Chemie, Georg-August-Universität Göttingen, Tammanstrasse 4, D-37077 Göttingen, Germany.
Abstract:
A straightforward synthesis toward the preparation of the rigid pyrazolate ligand L(H) featuring bipyridyl side-arms is described, starting from 2,2'-bipyridyl-N-oxide as the sole organic building block. In this context, optimized procedures for the synthesis of the organic intermediates 6-acetyl-2,2'-bipyridine 1 and 6-methylcarboxy-2,2'-bipyridine 2 are reported. The new ligand comprises two proximate terpyridine-like binding sites and is shown to form discrete [2 x 2]-grid complexes with CoII, MnII, and CuII in a highly selective self-assembly process, even in the presence of excess metal precursor. The thus obtained complexes [Co4L4][Na(NO3)4](NO3) (3), [Mn4L4](PF6)4 (4), and [Cu4L4](ClO4)4 (5) are fully characterized, including X-ray crystallographic analyses, and their magnetic properties are discussed. All three complexes show weak to moderate antiferromagnetic coupling between the four nuclei. The stability of the grid structures proved very high, as dissociation or exchange between metal ions in solution was not observed in a set of competition experiments.
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