An asymmetric mononuclear cobalt(II) compound derived from 3-bromo-pyridine-2,6-dicarboxylic acid involving in-situ hydrothermal decarboxylation: structure, magnetic property and Hirshfeld surface analysis

A new cobalt(II) compound with the formula [Co(5-Br-pyc)(2,2 ' -bipy)(H2O)(Cl)]center dot 2H(2)O (1 center dot H2O) (5-Br-Hpyc = 5-bromo-pyridine-2-carboxylic acid, 2,2 '-bipy = 2,2 '-bipyridine) has been hydrothermally synthesized and well characterized. The X-ray single-crystal diffraction analysis showed that 1.2H(2)O has crystallizes in the monoclinic system, space group P2(1)/c (no. 14). The Co(II) center was octahedrally bonded by one bidentate chelate 5-Br-pyc anion and one 2,2 '-bipy, one water molecule as well as one chloride anion to form the mononuclear structure of 1.2H(2)O. Complex 1.2H(2)O forms a 3D network through abundant O-H...O hydrogen bonds and pi...pi stacking interactions. Notably, the 5-Br-Hpyc ligand was in situ generated by decarboxylation of the 3-bromo-pyridine-2,6-dicarboxylic acid (3-Br-H(2)pydc) precursor selectively on 2-position under hydrothermal conditions. The magnetic properties, the Hirshfeld surface structure and the synthetic process for 1.2H(2)O have been carefully described and discussed.