Syntheses, crystal structures, and magnetic properties of two new manganese(II) complexes based on biphenyl-2,5,2′,5′-tetracarboxylic acid

Abstract

Two new complexes, [Mn(H₂bptc)(2,2′-bpy)₂] · 2H₂O (1) and [Mn₃(Hbptc)₂(2,2′-bpy)₃(H₂O)₈] · 2H₂O (2) (H₄bptc = biphenyl-2,5,2′,5′-tetracarboxylic acid, 2,2′-bpy = 2,2′-bipyridine), have been synthesized under hydrothermal conditions. Their structures have been characterized by single-crystal X-ray diffraction, elemental analyses, IR spectra, powder X-ray diffraction, and thermogravimetric analyses. Complexes 1 and 2 are both linked into 3-D supramolecular networks by non-covalent interactions (O–H ··· O, C–H ··· O, C–H ··· π, and π ··· π). Complexes 1 and 2 exhibit weak antiferromagnetic interactions.

Keywords:

• Manganese(II) complexes
• Biphenyl-2,5,2′,5′-tetracarboxylic acid
• Supramolecular structure
• Antiferromagnetic interactions

Acknowledgments

The authors gratefully acknowledge the financial support by the NSF of China (20771023), 863 Program (2007AA03z218) and analysis and testing foundation of Northeast Normal University.