Cadmium coordination polymers with different topologies depending on preparation methods: [CdL1.5(NO3)2], [CdL2(NO3)2] · (C6H6), and [CdL2(NO3)2] · 2(C4H8O) (L = 3-py–CHN–(CH3)C6H3–C6H3(CH3)–NCH–3-py)

Novel cadmium coordination polymers [CdL1.5(NO3)2] (1), [CdL2(NO3)2] · (C6H6) (2), and [CdL2(NO3)2] · 2(C4H8O) (3), which contain a common long 3,3′-bipyridyl-type ligand, were prepared from Cd(NO3)2 · 4H2O and ligand L (3-py–CHN–(CH3)C6H3– C6H3(CH3)–NCH–3-py). Whereas polymer 1 was prepared by solvothermal reactions, polymers 2 and 3 were prepared by layer diffusion. All have a repeating 84-membered ring unit. Polymer 1 has a non-interpenetrated 1-D ladder structure, and polymers 2 and 3 have a 2-D brick-wall structure. In particular, polymers 2 and 3 contain guest molecules (benzene (2) or THF (3)) in their frameworks, and the desorption–resorption behavior of the guest molecules is rather reversible.