New supramolecular organotin(IV)/-copper(I) cyanides containing the unique {CuI2(μ-CN)2} building block

Reaction of Me3SnCl/K3[Cu(CN)4] with the bipodal nitrogen bases (μ-L): bis(4-pyridyl)-trans-ethene (bpe), bis(4-pyridyl)-1,2-ethane (bpeH2), 4-cyanopyridine (cpy) and bis(4-pyridyl)-trans-1,4-divinylbenzene (pdvb) affords the new coordination polymers [CuCN·Me3SnCN·0.5bpe] (2), [CuCN·Me3SnCN·0.5bpeH2] (3), [CuCN·Me3SnCN·cpy] (4) and [CuCN·pdvb] (5). While 2 and 3 display layered structures with rhomboic {Cu2(μ-CN)2} units as basic building blocks (Cu⋯Cu distances: 2.634 and 2.758 Å, respectively), 4 crystallizes in a distorted-diamondoid structure 3∞[CuI{μ-CNSn(Me3)NC}{μ-cpy}] with four equivalent and independent, interlocking frameworks. In contrast, 5 consists of strongly corrugated, stapled sheets composed of parallel running –[Cu-pdvb]∞– zigzag chains tied together by CN bridges. Compounds 2 and 3 belong to the rapidly growing family of supramolecular assemblies containing the quite unusual [Cu2(μ-CN)2] unit the repeated appearance of which raises the question if cuprophilic interactions therein are the basic cause of the existence of that family.