Syntheses, structures and magnetic properties of two neutral coordination polymers of cobalt(II) containing a tailored aromatic diamine and pseudohalides as bridging units: Control of dimensionality by varying pseudohalide

Two neutral coordination polymers of the types 2D [Co(bnzd)(dca)2]n (1) and 3D [Co(bnzd)(N3)2]n (2) (bnzd = benzidine; dca = dicyanamide) have been synthesized and characterized. X-ray structural analyses reveal that each cobalt(II) center in 1 and 2 is hexacoordinated with octahedral geometry. Compound 1 has a 2D sheet structure with a (4,4) topology bridged through bidentate bnzd and double μ1,5 dca units. An extended 3D network structure in 2 is seen formed by μ1,3-azide and bidentate bnzd bridges. Variable-temperature magnetic susceptibility measurements of 1 and 2 show antiferromagnetic coupling among the cobalt(II) centers mediated through pseudohalide bridges.

Two neutral coordination polymers of the types 2D [Co(bnzd)(dca)2]n (1) and 3D [Co(bnzd)(N3)2]n (2) (bnzd = benzidine; dca = dicyanamide) have been synthesized through one-pot reactions of the building components, and characterized structurally and magneto-structurally.Figure optionsDownload as PowerPoint slideHighlights
► Two neutral cobalt(II) coordination polymers are isolated using benzidine and pseudohalide as bridging units.
► X-ray studies show interesting variation in architectures from a 2D (4,4) topology in dicyanamide to a 3D network in azide.
► The compounds show global antiferromagnetic interactions mediated through pseudohalide bridges.