Novel heterometallic Cu(II)/Cr(III) complex with unique open-chain N-ligand produced in conditions of direct template synthesis

The one-pot self-assembly reaction of copper powder, Reineckes salt, acetone and tris(2-aminoethyl)amine (tren) in dmso affords to obtain a heterometallic compound [Cu(trenac)][Cr(NCS)4(NH3)2](NCS) · 6dmso with novel Schiff-base ligand N-(2-{[(1E)-3-amino-1,3-dimethylbutylidene]amino}ethyl)-N-(2-aminoethyl)ethane-1,2-diamine (trenac). The ligand trenac is generated by metal-directed condensation of tren, acetone and ammonia, formed during the synthetic procedure. X-ray structural investigations showed that the complex consists of [Cu(trenac)]2+ cations, anions of the Reineckes salt [Cr(NCS)4(NH3)2]−, uncoordinated thiocyanate groups and dmso molecules, which are held together by electrostatic forces and hydrogen-bonded interactions. The compound was characterized by EPR spectroscopic and magnetic susceptibility measurements.