In situ hydrothermal synthesis of two novel Cd(II) coordination compounds

Hydrothermal in-situ reactions of 4,4′-bis(3,3′-dicyano)pyridine (pydcy) with Cd(NO3)2·6H2O under the similar reaction condition but different solvent media result in two new compounds [C48H32Cd2N8O18](1) and [C17H13CdN3O5](2). Compound 1 features a new dimeric carboxylate bridged structure, while compound 2 gives a 3D framework with large hexagon channels embodied with water molecules. Topology analysis of 2 defines a type of {83} etb topology. TGA and XRPD analysis indicated that the guest water molecules in 2 can be removed to result in a nanoporous network. Both compounds exhibit intense fluorescence at room temperature, which may originate from the ligand-to-metal charge transfer (LMCT) state.