A Series of Lead(II) Complexes with π−π Stackings: Structural Diversities by Varying the Ligands

Twelve structurally diverse complexes, [Pb2(pzp)2(adip)(NO3)2] 1, [Pb(pzp)(glu)] 2, [Pb(pzp)(chdc)]·[Pb(pzp)(chdc)]·pzp·H2O 3, [Pb2(ndc)2(pzp)2(H2O)]·0.5H2O 4, [Pb(pzp)(1,3-bdc)(H2O)0.5]·H2O 5, [Pb(pzp)(1,2-bdc)]·H2O 6, [Pb2(ptc)2(adip)(NO3)2] 7, [Pb(ptc)(glu)] 8, [Pb(ptc)(chdc)] 9, [Pb(ptc)(dpdc)]2 10, [Pb(ptc)(1,3-bdc)]·2.5H2O 11, and [Pb(ptc)(1,4-bdc)]·0.75H2O 12, where H2adip = adipic acid, H2glu = glutaric acid, H2chdc = 1,4-cyclohexanedicarboxylic acid, H2ndc = 1,4-naphthalenedicarboxylic acid, 1,4-H2bdc = benzene-1,4-dicarboxylic acid, H2dpdc = 2,2′-diphenyldicarboxylic acid, 1,3-H2bdc = benzene-1,3-dicarboxylic acid, 1,2-H2bdc = benzene-1,2-dicarboxylic acid, pzp = pyrazino[2,3-f][1,10]phenanthroline, and ptc = 2-phenyl-1H-1,3,7,8,-tetraaza-cyclopenta[l]-phenanthrene, have been hydrothermally synthesized. Compounds 7 and 10 possess dinuclear structures, which are further extended by π−π interactions to form supramolecular layers and chains, respectively. 1−6, 8−9, and 11−12 feature chain structures, which are then stacked by π−π interactions to result in 2D or 3D supramolecular architectures. The structural differences among such complexes show that the organic acids and neutral chelating ligands have important influences on the structures.