Self-assembly of three hetero- and homopolynuclear cyanide bridged complexes of FeII–CuI and CuI: hydrothermal syntheses, structural characterization and properties

Reaction of CuII, K3 [Fe(CN)6] and bidentate diimine ligands by hydrothermal synthesis under different conditions affords one novel heteronuclear FeII–CuI complex, {[Fe2II(bipy)4(μ-CN)4Cu2I(CN)2]·H2O}n(1) (bipy = 2,2′-bipyridine), and two homonuclear CuI complexes, [CuI(μ-CN)(bipy)]n (2) and [Cu3I(μ-CN)3(phen)3]n (3) (phen = 1,10-phenanthroline). Although all the three complexes are 1D cyanide bridged helical chains, they have different helicoids of pseudo-square, pseudo-trigonal and head-to-head bistrigonal for 1, 2 and 3, respectively. The structure of 1 is extended to 2D hexagonal meshed layers by the hydrogen bonding between terminal cyanides and lattice water molecules, which also contain π–π interactions between adjacent sheets. CuI ions in 1 are distorted trigonal planar coordinated by two bridging cyanides and one terminal cyanide, whereas that in 2 and 3 are pseudo-tetrahedral coordinated by two bridging cyanides and two N atoms of a diimine. Both the latter homometallic polymers exhibit similar chain structure, and these chains are close packed with their six adjacent chains in a parallel fashion along the c-axis to form a honeycomb network. It should be noted that complex 1 is the first cyanide bridged FeII–CuI complex of helical chain structure. The spectroscopic properties of complexes 1–3 have also been investigated.

Reaction of CuII, K3[Fe(CN)6] and diimine ligands by hydrothermal techniques under different conditions affords one novel FeII–CuI and two CuI cyanide bridged complexes. The three compounds are 1D helical chains with different helicoids. Their spectroscopic properties have also been investigated.Figure optionsDownload as PowerPoint slide