Two Unprecedented Entangled Metal-Olsalazine Complexes with Coexistence of 2D → 3D Polycatenation and meso-Helix

Rational self‐assembly of the anti‐inflammatory drug olsalazine (H4osa) with a cobalt salt in the presence of linear bidentate ligands yields two novel metal–drug complexes[Co(H2osa)(bpp)] (1) and [Co2(osa)(bpy)2(H2O)4] (2) [bpp = 1,3‐bis(4‐pyridyl)propane, bpy = 4,4′‐bipyridine]. Their structures were determined by single‐crystal X‐ray diffraction and further characterized by elemental analysis, IR spectroscopy, X‐ray powder diffraction, and thermogravimetric analysis (TGA). Compound 1 displays a new 2D → 3D parallel polycatenation of undulating (4,4) layers, whereas 2 exhibits an unusual 2D → 3D inclined polycatenation of (6,3) layers. To the best of our knowledge, they represent the first examples of metal–drug complexes that have both polycatenane and meso‐helix characteristics. The magnetic properties of 1 and 2 have been studied by measuring their magnetic susceptibility in the temperature range of 2–300 K. Two unprecedented polycatenated metal–olsalazine complexes, containing rare meso‐helices, are reported, which represent the first examples of entangled metal–olsalazine complexes.