Syntheses of two copper(II) coordination polymers from a morpholine-based tridentate Schiff base ligand: crystal structures and magnetic properties

Two new one-dimensional (1-D) end-to-end azido and thiocyanato bridged Cu(II) coordination polymers, [Cu(L)(mu-1,3-N-3)](n)(ClO4)(n) (1) and [Cu(L)(mu-1,3-NCS)](n)(ClO4)(n) (2) with a morpholine-based tridentate N,N,N-donor Schiff base ligand (1-methyl-1H-imidazol-2-yl)-N-[2-(morpholin-4-yl)ethyl]methanimine, L) have been synthesized. Compounds 1 and 2 have been characterized by elemental analyses and spectroscopic techniques. The X-ray single crystal structures of 1 and 2 show the formation of regular zigzag chains with mu-1,3-azido and mu-1,3-thiocyanate bridges, respectively. Variable temperature (2-300 K) magnetic studies indicate that 1 shows a ferromagnetic intrachain exchange interaction with g = 2.135(2) and J = 2.13(2) cm(-1), while in 2 this interaction is antiferromagnetic with g = 2.1412(3) and J = -0.277(2) cm(-1). X-band EPR spectra of 1 and 2 in frozen (143 K) DMF solution corroborate our magnetic studies.