Two three-dimensional pillared metal–olsalazine complexes based on infinite rod-shaped secondary building units

The first two three-dimensional (3D) pillared metal–olsalazine complexes, namely [Co(osa)0.5(bim)0.5(H2O)] (1) and [Cd(osa)0.5(bim)0.5(H2O)] (2) (H4osa = 3,3-azo-bis(6-hydroxybenzoic acid), bim = 1,4-bis(imidazol-1-yl)butane) have been hydrothermally synthesized and further characterized by single-crystal X-ray diffraction, powder X-ray diffraction, elemental analysis, IR spectra and TG analyses. Compounds 1 and 2 are isostructural, and their frameworks are composed of infinite rod-shaped secondary building units (SBUs) that are bridged by osa ligands to form 2D layers, which are further pillared by bim ligands in the third dimension. To the best of our knowledge, it is the first time that 3D pillared-layer frameworks involving infinite rod-shaped SBUs have been obtained in the realm of metal–olsalazine complexes. The magnetic property of 1 and photoluminescence of 2 have also been investigated.