A new luminous hexacoordinated coordination polymer of cadmium(II) containing benzidine and dicyanamide as bridging units

A neutral hexacoordinated 2D coordination polymer [Cd(bnzd)(dca)2]n (1) [bnzd = benzidine and dca = dicyanamide] is prepared using a one-pot reaction of the building units and characterized. X-ray structural analysis reveals each cadmium(II) center to adopt a distorted octahedral geometry with a CdN6 chromophore bound by two N atoms of two different bnzd and two sets of double μ1,5 dca units affording a 2D sheet structure with a (4,4) topology. In the crystalline state, multiple intermolecular N―H⋯N hydrogen bonds result in a 3D network structure. 1 displays intraligand 1(π–π⁎) fluorescence in DMF solution at room temperature.