Six new inorganic–organic hybrids based on rigid triangular ligands: Syntheses, structures and properties

•MOFs based on POMs have been prepared.•Six new compounds based on rigid triangular N-containing ligands.•The adjacent POMs only share the oxygen atom to form a 1D inorganic Keggin chains.

Six new inorganic–organic hybrids based on rigid triangular N-containing ligands, NaCuI2(tib)4(H2O)4[H2PWVWVI11O40][H2PWVI12O40]·6H2O (1), CuII3(tib)4Cl4[H2PWVI12O40]2·4H2O (2), Co(tib)2[PWV3WVI9O38]·5H2O (3), CuII3(tib)2[P2MoVI5O22(O2)]·4H2O (4), Mn(pytpy)2MoVI4O13 (5) and Co(pytpy)2MoVI4O13 (6) (tib=1,3,5-tris(1-imidazolyl)benzene, pytpy=4’-(4”-pyridyl)2,4’:6’,4”-terpyridine), have been hydrothermally synthesized. Single crystal X-ray diffraction studies revealed that compounds 1–4 display two-dimensional (2D) layered structures, and in compounds 1–3, the adjacent Keggin anions link with each other by W–O–W covalent interactions to form 1D inorganic chains. Compounds 5–6 are 3D “pillar-layer” frameworks based on bimetal–oxide layers pillared by the pytpy ligands. The compounds have been characterized by elemental analysis, powder X−ray diffraction, X-ray photoelectron spectroscopy and thermo gravimetric analyses. Moreover, the electrochemical and catalytic properties of compound 1 have been investigated as well.

Graphical abstractSix new inorganic–organic hybrids based on rigid triangular N-containing ligands have been obtained under hydrothermal conditions and characterized by single-crystal X-ray diffraction analyses, elemental analyses, IR spectra, and thermogravimetric (TG) analyses. Compounds 1–4 display two-dimensional (2D) layers structure, and in compounds 1–3, the adjacent Keggin anions link with each other by W–O–W covalent interactions to form 1D inorganic Keggin anions chains. Compounds 5–6 are 3D “pillar-layer” frameworks based on bimetal–oxide layers pillared by the pytpy ligands.Figure optionsDownload full-size imageDownload as PowerPoint slide