Six copper(II) compounds 1-6 were synthesized. Adipic acid (C$_6$H$_{10}$O$_4$ = H$_2$L) and one of the pyridine ligands (1- nicotinamide, 2- isonicotinamide, 3- 2-hydroxypyridine, 4- 3-hydroxypyridine, 5- 4-hydroxypyridine and 6- 2-aminopyridine) were used in all cases. The adipic acide is a diprotic aliphatic compound with the formula COOH(CH$_2$)$_4$COOH. All syntheses took place in water. The isolated compounds were analyzed using X-ray powder diffractio, XRD, though a match in the CSD database was found only for compound 1, having formulae {[CuL(C$_6$H$_6$N$_2$O)$_2$](H$_2$O)}$_n$. No known structures were found for the other compounds 2-5. The IR analysis was most helpful in determining the presence of relevant bonds associated with the starting compounds, or weather these compounds are present in the isolated products 1-6. UV-Vis analysis revealed that the compounds have different coordination spheres. This was noticed by their different colors and the differences in their electronic spectra. As well there are different positions of d-d band in the products 1-6.
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