Novel cadmium–organic frameworks with nitrilotriacetate

Novel cadmium–organic frameworks incorporating nitrilotriacetate (NTA 3− ) and BPY (4,4′‐bipyridine) were synthesized under hydrothermal conditions and structurally characterized by single‐crystal x‐ray crystallography and other techniques. The crystal structure of CUmof‐7, [Cd 4 (BPY) 5 (NTA) 2 (H 2 O) 4 ]ċ(NO 3 ) 2 ċ(H 2 O) x , consists of infinite 2D cationic bilayers stacked along the c direction, and perforated by wide tubular channels filled with nitrate ions and highly disordered water molecules. CUmof‐8, [Cd 4 (BPY) 4 (NTA) 2 (H 2 O) 10 ]ċ(BPY)ċ(NO 3 ) 2 ċ (H 2 O) 8 , is a 1D metal–organic polymer produced by the self‐assembly of a bimetallic secondary building unit into a cationic chain, $[{\rm Cd}_2({\rm BPY})_2 ({\rm NTA})({\rm H}_{2} {\rm O})_5]_n^{n+}$ . NTA 3− appears in both crystal structures as an effective polydentate ligand which traps the Cd 2+ metal ions inside three chelate five‐membered rings, eliminating available coordination sites and favouring the formation of 1D polymers (for CUmof‐8). Copyright © 2003 John Wiley & Sons, Ltd.