Supramolecular architecture constructed from the hemidirected lead(II) complex with N'-(4-hydroxybenzylidene)isonicotinohydrazide

In this work we have directed our attention to the N'-(4-hydroxybenzylidene)isonicotinohydrazide (HL) as a linker for the production of a Pb(II) extended structure. As a result, discrete homoleptic coordination compound [PbL2] with two deprotonated ligands L was isolated. All the covalent Pb-N/O bonds are collected on a half of hemisphere of the globe of the coordination sphere yielding a large gap in the coordination sphere of Pb(II). This enables a close approach of the amide nitrogen atom from an adjacent molecule with the formation of a tetrel bond of about 3.0 angstrom, yielding 1D polymeric chains. These chains are interlinked via intermolecular O-H center dot center dot center dot N hydrogen bonds and C-H center dot center dot center dot pi interactions, yielding a 3D structure. Considering O-H center dot center dot center dot N intermolecular hydrogen bonds, molecules of [PbL2] form a single helical structural unit of a hexagonal shape. These motifs are mutualy interpenetrated and the overall 3D network of [PbL2] belongs to a ThSi2 network. The Pb center dot center dot center dot N tetrel bonding interaction was stiduied in details using DFT.