Synthesis, thermal properties, and biological study of metal(II) nicotinamide complexes containing fumarate dianion and fumaric acid: Crystal structure of [Ni(H₂O)₄(nia)₂](fum)·(H₂fum)

ABSTRACT

New divalent transition metal nicotinamide (nia) complexes containing fumarate (fum) dianion and fumaric acid (H₂fum), [M(H₂O)₄(nia)₂](fum)·(H₂fum) [M = Co (1), Cu (2), and Ni (3)] have been synthesized.The compounds were characterized by elemental analyses, infrared, UV-vis, XRPD, and TGA. Structural analysis of 3 using single-crystal X-ray diffraction technique revealed that the Ni(II) ion is coordinated by four aqua and two nia ligands in an octahedral geometry. The structure of 3 is completed with fumarate (fum²⁻) dianion acting as a counterion while fumaric acid (H₂fum) is present as a molecule of solvation. The three complexes were investigated for biological activities.

KEYWORDS:

• Fumarate complexes
• nicotinamide
• crystal structure
• XRPD analysis
• biological activity

Acknowledgments

The authors are grateful to Dr. Michael Worle from ETH, Zurich, for help with structure determination of compound 3 during the 2013 Zurich School of Crystallography, Institute of Organic Chemistry, University of Zurich.