Structures and theoretical studies of three copper(II) complexes containing 2,2′-dipyridylamine and acrylato or methylacrylato ligands

A series of new complexes of copper(II): [Cu(CH2=C(Me)CO2)2(dpa)]·H2O (1), [Cu(CH2=CHCO2)2(dpa)]·H2O (2), Cu(CH3CH=CHCO2)2(dpa)(H2O) (3) (dpa = 2,2′-dipyridylamine) have been prepared and characterized by elemental analysis, IR spectra, thermal analysis, density functional theory (DFT) calculations and X-ray structure analysis. The crystal structures of 1 and 2 consist of neutral [Cu(L)2(dpa)] (L = CH2=C(Me) and CH2=CH ) units and one lattice water molecule in the unit cell, while in 3 the water molecule is found to coordinate to copper(II). The mononuclear units of 1 and 2 are linked via a similar triple-hydrogen-bonding uncoordinated water molecule into different supramolecular structures, 1D double chains for 1 and a 2D supramolecular network for 2. A detailed crystal structure analysis of 2 revealed that the presence of the C–H ··· O and C–H ··· C hydrogen bonds appear to be responsible for the difference in supramolecular structures differences between 1 and 2. In 3, 1D double chains are formed throu...