A series of three dimensional lanthanoid(III)-metal-organic frameworks with zwitterionic linker

Abstract

A series of isostructural 3D lanthanoid coordination polymers, {[Ln(µ₄-cbpy)₂]Br·xsolvent}_n (Ln = La(1), Pr(2), Nd(3), Sm(4), Gd(5), Tb(6), Dy(7) and Ho(8), (H₂cbpy)Br = 4-carboxy-1-(4-carboxybenzyl)pyridinium bromide), have been solvothermally synthesized and characterized by single-crystal X-ray diffraction, IR and elemental analysis. Powder X-ray diffraction (PXRD) and thermal analyses (TG, DTA and DTA) of 1–8 were also investigated. The single crystal X-ray diffraction analyses revealed that 1–8 were isostructural and crystallized in the monoclinic space group C2/c. In the complexes, each cbpy^– acts as a tetrakis(monodentate) to connect to four Ln(III) ions. A pair of Ln(III) ions are coordinated by four carboxylate oxygen atoms to form paddle-wheel {Ln₂(RCOO)₄} secondary building units which are connected by four cbpy^– ligand to form a 3D structure with scu topology.

Graphical Abstract

Keywords:

• Zwitterionic complexes
• lanthanoid complexes
• 3D complexes
• coordination polymers

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work has been supported by Eskisehir Osmangazi University Scientific Research Projects Coordination Unit under grant number 201919C102.