C−H···Br-M Interactions at Work: Tetrabromometalates of the Bolaamphiphilic <i>N</i>,<i>N</i>‘-Dodecamethylenedipyridinium Cation

The organic−inorganic hybrid salts [Py−C12−Py][MX4] (M = Pd, Cu; X = Cl, Br) were prepared by reaction of the N,N‘-dodecamethylenedipyridinium cation [Py−C12−Py]2+ and the appropriate halide metal salt. The crystal structures of the bromide derivatives [Py−C12−Py][PdBr4] (3) and [Py−C12−Py][CuBr4] (4) were determined by X-ray crystallography. The presence of several C−H···Br−M contacts between organic cations and inorganic anions leads to segregation of the polymethylene chains. These are arranged in columns which are surrounded by bound pyridinium cation headgroups and isolated tetrabromometalates. The role of C−H···Br−M interactions in crystalline species has been investigated through a CSD search and subsequent analysis.