pH-Dependent synthesis of two new lead(II) coordination polymers with 4-aminoantipyrine and 5-nitroisophthalate ligands

摘要: Two novel lead(II) coordination polymers with the same mixed ligands, [Pb(AAP)(NIP)]n (I) and {[Pb(AAP)(NIP)] · 2H2O}n (II) (AAP = 4-aminoantipyrine NIP2− 5-nitroisophthalate), were prepared by controlling pH value of reaction mixture. Complexes I II characterized X-ray single-crystal diffraction analyses (CIF files CCDC nos. 936101 936102 (II)). Complex terminal AAP molecule displays a linear chain hemidirected Pb2+ ions connected bis-bidentate chelating-NIP2− anions. By contrast, complex exhibits dimeric {Pb2(AAP)2}-based coplanar layer extended bidentate chelating-bidentate chelating bridging-NIP2− Obviously, pH-directed structural difference is dominated competitive binding modes carboxylate groups ligands. Both complexes display different thermal stability due to similar emissions originated from intra- and/or inter-ligand electron transfer, suggesting their potential application as luminescent materials.