Synthesis, structure and magnetic properties of a 1D coordination polymer of Cu(II) containing phenoxido and dicyanamido bridging groups

A new CuII 1D coordination polymer, {[Cu2(L)(μ1,5-dca)]2·2(CH3OH)}n (1), containing the carbohydrazide based ligand (H3L = bis-[(E)-N′-(2-hydroxybenzylidene)]carbohydrazide) and the dicyanamide (dca) bridging group has been synthesized and characterized by magnetic measurements, single crystal X-ray diffraction and other spectroscopic methods. X-ray analysis reveals that the ligand coordinates to the CuII ion as a hexadentate trinegative N3O3-donor ligand. Tetranuclear copper(II) units with double phenoxido bridges are formed, connected and extended by two μ1,5-dca anions, forming a 1D polymeric structure. The magnetic measurements showed global antiferromagnetic interactions with two coupling constants between “outer” (J = −87 ± 2 cm−1) and “inner” (J′ = −129 ± 2 cm−1) copper pairs in tetranuclear units. The dicyanamide, adopting the end-to-end bridging mode (metal–metal separation of ca. 8.062(5) Å), has presented poor efficiency in mediating magnetic interactions.

Graphical abstractThe structure of a new 1D coordination polymer of CuII with a carbohydrazone based ligand and dicyanamide bridges was determined. The magnetic and spectroscopic properties of the coordination network were studied.Figure optionsDownload full-size imageDownload as PowerPoint slide