Two new CuII 1D-coordination polymers containing 1,4-pyrazine-2,3-dicarboxylic acid, 2-aminopyridine, and 5-bromo-6-methyl-2-(4-methylpiperazine-1-yl)pyrimidine-4-amine: X-ray crystal structure, spectroscopic and magnetic studies

In this work, we report the design and synthesis of two 1D-coordination polymers under ambient condition namely {[H2-apy](2)[Cu(pyzdc)(2)]}(n) (1) and {[Hbmpa](2)[Cu(pyzdc)(2)]center dot 2H(2)O}(n) (2), which have been pre-pared by the reaction between CuCl2 center dot 2H(2)O, 1,4-pyrazine-2,3-dicarboxylic acid (H2pyzdc) and 2-aminopyridine (2-apy) or 5-bromo-6-methyl-2-(4-methylpiperazine-1-yl) pyrimidine-4-amine (bmpa). The compounds have been structurally determined by single crystal X-ray diffraction analyses, elemental analyses and IR spectra. These coordination polymers consist of [Cu(pyzdc)(2)](2) chains and discrete positively charged 2-apy or bmpa fragments. In 1 and 2, the variable temperature magnetic measurements show very weak antiferromagnetic interactions between the Cu-II centers. (C) 2012 Elsevier B.V. All rights reserved.