2D frameworks self-assembled from a hydrazone ligand and azide salts: synthesis, structures, and luminescent property

摘要

Three metal-organic coordination polymers {[Cu(L)(N 3 )]·(H 2 O) 0.25 } n ( 1 ), {[Zn(L)(N 3 )]·(H 2 O) 0.5 } n ( 2 )and [Cd 2 (L) 2 (N 3 ) 2 (H 2 O)] n ( 3 )have been synthesized from hydrazone ligand N ′-(1-(pyrazin-2-yl)ethylidene)isonicotinohydrazide (HL ), NaN 3 and corresponding metal nitrates. Complexes were characterized by elemental analysis, IR spectroscopy and single-crystal X-ray diffraction. All three complexes feature 2D coordination network in which L 1– acts as NNON tetradentate ligand and azide acts as end-on bridging ligand. In complexes 1 and 2 , only intra-sheet hydrogen bonding interactions are found, while the hydrogen bonding interactions between water molecules and host framework result in 3D network for 3 . In addition, complexes 2 and 3 exhibited intense fluorescent emissions in the solid state at room temperature.