New Inorganic−Organic Hybrid Supramolecular Architectures Generated from 2,5-Bis(3-pyridyl)-3,4-diaza-2,4-hexadiene

Abstract

Two new metal coordination polymers with interesting supramolecular architectures, [Mn(H2O)4(L1)]n(ClO4)2n·2nL1 (1) and [Ag(L1)(NO3)]n (2) [L1 = 2,5-bis(3-pyridyl)-3,4-diaza-2,4-hexadiene], have been synthesized and characterized structurally. Complex 1 exhibits a novel supramolecular layer architecture sustained by the concurrence of coordination bonds, hydrogen bonds, and π−π stacking interactions: the Mn(II) ions are coordinated by water molecules and the bridging μ2-L1 ligands to yield one-dimensional (1D) zigzag [Mn(H2O)4(L1)]n coordination chains; the free L1 ligands are hydrogen bonded to half of the coordinated water molecules and form π−π stacking triads with the bridging ligands, generating three-strand supramolecular ribbons; and the perchlorate ions form hydrogen bonds with the remaining coordinated water molecules, interlinking the ribbons into an unusual triple-decked supramolecular layer. In complex 2, each Ag(I) ion is tetracoordinated by two μ2-L1 and two μ2-nitrate ligands. The μ2-L1 ligands connect the metal ions into infinite 1D helix-like AgL1 chains, and the μ2-nitrate ions interlink the chains into undulate coordination layers. C−H···O weak hydrogen bonds exist between neighboring layers in 2.