New 3,5-dimethylpyrazole copper(II) compounds with a variety of hydrogen bonds, synthesized by using a dehydrating agent: Synthesis, characterization, structures and intermolecular interactions

Six new mononuclear compounds have been synthesized with formula [Cu(Hdmpz)4(BF4)2] (1), [Cu(Hdmpz)4(ClO4)2] (2), [Cu(Hdmpz)4(CF3SO3)2] (3), [Cu(Hdmpz)4(NO3)2] (4), [Cu(Hdmpz)3(NO3)2] (5), [Cu(Hdmpz)4(H2O)](CF3SO3)2 (6) (Hdmpz = 3,5-dimethylpyrazole). For five of them a X-ray crystal structure was performed. Special attention is given to the differences in hydrogen bonding, which do vary strongly with varying counter anions.