A series of 2D and 3D coordination polymers containing multicore Mn-carboxyl chain and flexible polycarboxylate ligands: synthesis, structure, and magnetic properties

Abstract

We report the synthesis, crystal structures, and magnetic properties of a series of two-dimensional (2-D) and three-dimensional (3-D) coordination polymers (CPs). A solvothermal reaction of manganese metal salts with 4,4′-oxydibenzoic acid (H₂oba), 4,4′-methylenebis(oxy) dibenzoic acid (H₂mba), 4,4′-(propane-1,3-diylbis (oxy))dibenzoic acid (H₂pba) or 1,4-bis (1H-imidazol-1-yl)-butane (bib) gives five new non-interpenetrating CPs, [Mn₂(oba)₂(CH₃OH)(H₂O)] (1), [Mn₆(oba)₆(bib)(DMF)₂(H₂O)₄] · (DMF)₂(CH₃OH) (2), [Mn₄(mba)₄(bib)(CH₃OH)] (3), [Mn₇(pba)₇ (bib)(H₂O)₄] · (H₂O)₃(DMA)(CH₃OH)_0.5 (4), and [Mn₇(pba)₇(H₂O)₆](DMA)₃ (5). The X-ray crystal structural analyses revealed that 1, 4, and 5 are 2-D layers, whereas 2 and 3 are 3-D frameworks with 1-D Mn-carboxylate chains. In 1, 2, 4, and 5, the 1-D Mn-carboxylate chains are formed by flexible carboxylate ligands and Mn ions; these were then linked by organic ligands in different directions, leading to the formation of 2-D and 3-D frameworks. Furthermore, IR, PXRD, elemental analysis, TGA, and magnetic properties have been investigated.

Graphical Abstract

Keywords:

• CPs
• Mn-carboxyl chain
• structure
• magnetic properties
• multicore Mn

Acknowledgements

We thank LetPub (www.letpub.com) for its linguistic assistance during the preparation of this manuscript.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by grants from the Colleges and Universities’ Scientific Research Project of Inner Mongolia Autonomous Region (NJZY17401), National College Students Innovation and Entrepreneurship training program (201914532003), Scientific Research Project of Ordos Institute of Technology (KYYB2017010, KYYB2018005), Research Project of Teaching Reform in Higher Education (20190103) and Innovation Foundation for Students of Ordos Institute of Technology (201619001, 201719013, 20180307).