Hydrogen Bonding Interactions Directed Various Supramolecular Networks Based on Octamolybdates and Different Flexible Bis-Pyridyl-Bis-Amide Ligands

Four new inorganic–organic hybrid supramolecular architectures constructed from octamolybdates (Mo 8 O 26 ) and different bis-pyridyl-bis-amide ligands, (3-dpye = N,N ′-bis(3-pyridinecarboxamide)-1,2-ethane, 4-dpye = N,N ′-bis(4-pyridinecarboxamide)-1,2-ethane, 3-dpyp = N,N ′-bis(3-pyridinecarboxamide)-1,3-propane, 4-dpyp = N,N ′-bis(4-pyridinecarboxamide)-1,3-propane): (3-H 2 dpye)(γ-Mo 8 O 26 ) 0.5 ( 1 ) and (4-H 2 dpye)[(4-dpye)(γ-Mo 8 O 26 )] 0.5 ·2H 2 O ( 2 ) and [(3-H 2 dpyp) 2 (β-Mo 8 O 26 )]·2H 2 O ( 3 ) [(4-H 2 dpyp) 2 (β-Mo 8 O 26 )]·2H 2 O ( 4 ), have been hydrothermally prepared and structurally characterized by single crystal X-ray diffraction analyses. Compound 1 exhibits a 3D 6-connected supramolecular framework assembled from 1D γ-Mo 8 O 26 inorganic chains and 3-H 2 dpye molecules. Compound 2 consists of an uncommon 1D γ-Mo 8 O 26 –4-dpye inorganic–organic hybrid chain connected by Mo–N bond, which are extended by 4-H 2 dpye molecules to a 3D 3,8-connected supramolecular framework. Compounds 3 and 4 show 3D 6,6-connected supramolecular framework and 2D 3,6-connected supramolecular layer based on β-Mo 8 O 26 anions and 3/4-H 2 dpyp molecules via hydrogen bonds, respectively. The different bis-pyridyl-bis-amide ligands, isomers of octamolybdates and hydrogen bonding interactions in the title compounds show great effects on the final supramolecular networks. The electrochemical, electrocatalytic and photocatalytic activities of compounds 1–4 have been investigated.