Synthesis and Characterization of a 2D Cobalt(II) Coordination Polymer Containing the Adiponitrile Ligand

The cobalt(II) coordination polymer [Co(ADN) 3 ][FeCl 4 ] 2 ( 1 ), which contains a flexible dinitrile bridging ligand was synthesized at room temperature from the 1:2:3 reaction of CoCl 2 , FeCl 3 , and adiponitrile (ADN) in CH 3 NO 2 . The compound was characterized by spectroscopic methods and single‐crystal X‐ray diffraction. The structure of 1 consists of a 2D sheet structure of [Co(ADN) 3 ] 2+ cations, the charge balance is maintained by [FeCl 4 ] – anions. Each central Co II atom is coordinated by six nitrogen atoms from four gauche ‐ and two anti ligands, adopting a distorted octahedral arrangement. The [FeCl 4 ] – anions sit in channels created by the [Co(ADN) 3 ] 2+ cations, and link the 2D sheets into a 3D structure by weak C–H ··· Cl hydrogen bonds. The framework structure of 1 is thermally stable up to 285 °C.