Structure of the first dinuclear Ni(II) complex with an azapurine derivative (the anionic form of 4,6-dimethyl-1,2,3-triazolo[4,5-d]pyrimidin-5,7-dione)

The first dinuclear nickel complex with an azapurine derivative is reported. The crystal structure consists of discrete [Ni2(dmax)3(H2O)2(dben)2]+ cations, the charge of which is balanced by interstitial dmax anions, where dmax = 4,6-dimethyl-1,2,3-triazolo[4,5-d]pyrimidin-5,7-dionato and dben = N,N′-dibenzylethylenediamine. The nickel centres are bridged by three heterocyclic anions through two nitrogen atoms of their triazole ring. The presence of the bulky auxiliary ligand clearly favours the bridging behaviour of the main ligand, probably by hindering the formation of H-bonds with dmax N atoms as acceptors. H-bonding is however, the main packing interaction, with eight different well defined intermolecular H-bonds that build a 3-D network that is analysed.

Graphical AbstractDescription of the first nickel complex with three azapurine derivatives acting as bridge. Analysis of its 3D hydrogen-bond network as well as the influence of a bulky auxiliary ligand in the coordination behaviour of this azapurine derivative.Figure optionsDownload as PowerPoint slide