MOF Formation vs. Reversible High Ligand Uptake in Anhydrous Halides: Two Opposing Aspects of ³_∞[La₂Cl₆(4,4'-bipy)₅]•4(4,4'-bipy)

Christoph J. Höller (1) , Philipp Matthes (2) , Jens Beckmann (3) , Klaus Mueller-Buschbaum (2)

1 Department Chemie und Biochemie
2 Department Chemie und Biochemie
3 Institut für Chemie und Biochemie

Construction of the framework structure ³_∞[La₂Cl₆(4,4'-bipy)₅]•4(4,4'-bipy) (1), bipy = 4,4´-bipyridine, C₁₀H₈N₂, is achieved by reaction of the anhydrous halide LaCl₃ with molten 4,4´-bipyridine. Five equivalents of bipyridine are used for the framework construction linking LaCl₃ units to give an extended, three-dimensional MOF. Furthermore four additional equivalents of bipyridine per LaCl₃ unit are incorporated within the crystalline MOF, which is thereby completely filled with bipy molecules. This compound formation results in the extraordinary high uptake of nine equivalents of bipyridine per equivalent of the formula LaCl₃ and a volume increase of eight times the volume of LaCl₃. Further heating of the MOFs results in a stepwise release of all nine equivalents of bipyridine and re-formation of the anhydrous chloride at 425 °C. Formation and disassembly can be run in cycles and are reversible. Thus two interesting yet opposing aspects are the reversible construction and disassembly of the MOF framework.

Mots clés: Physical Sciences

Christoph J. Höller, Philipp Matthes, Jens Beckmann, Klaus Mueller-Buschbaum. MOF Formation vs. Reversible High Ligand Uptake in Anhydrous Halides: Two Opposing Aspects of ³_∞[La₂Cl₆(4,4'-bipy)₅]•4(4,4'-bipy). Journal of Inorganic and General Chemistry / Zeitschrift für anorganische und allgemeine Chemie, 2009, 636 (2), pp.395. ⟨10.1002/zaac.200900359⟩. ⟨hal-00542553⟩