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

Abstract

Two new one-dimensional (1-D) end-to-end azido and thiocyanato bridged Cu(II) coordination polymers, [Cu(L)(µ-1,3-N₃)]_n(ClO₄)_n (1) and [Cu(L)(µ-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 µ-1,3-azido and µ-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.

GRAPHICAL ABSTRACT

Keywords:

• Copper
• Schiff base
• crystal structure
• magnetic properties

Disclosure statement

There is no conflict of interest to declare.

Acknowledgement

We are thankful to the reviewers for their valuable suggestions and comments to put the work into scientific context.

Additional information

Funding

N.K.M. thankfully acknowledges the financial support received from the UGC, New Delhi, India in terms of senior research fellowship.