New pillared dioxomolybdenum(VI) complexes with ONS donor ligands and 4,4 '-azopyridine spacer: 3D metal-organic supramolecular architectures and DFT calculations

作者：Biswal Debanjana; Pramanik Nikhil Ranjan^*; Chakrabarti Syamal^*; Drew Michael G B

来源：Inorganica Chimica Acta, 2016, 451: 92-101.

DOI：10.1016/j.ica.2016.07.004

• Dioxomolybdenum(VI)
• Schiff base ligand
• 4,4 '-Azopyridine
• Crystal structure
• Supramolecular interactions
• DFT calculations

Two new pillared binuclear dioxomolybdenum(VI) complexes [(MoO2L1)(2)(4,4'-azpy)] (1) and [(MoO2L2)(2)(4,4'-azpy)] (2) have been synthesized by the reaction of MoO2(acac)(2) with Schiff base ligands (H2L1 and H2L2) derived from 2-hydroxyacetophenone and S-benzyl/S-methyl dithiocarbazates respectively and 4,4'-azopyridine as a spacer. Crystal and molecular structures of the investigated binuclear complexes 1 and 2 were determined by single crystal X-ray diffraction. The two complexes have similar centrosymmetric dimeric structures in which each molybdenum atom occupies distorted octahedral six-coordinate environments being bonded to a dianionic tridentate ONS donor ligand via phenolate oxygen, imine nitrogen and thioenolate structure as well as two terminal oxygen atoms and a nitrogen atom of the bridging 4,4'-azpy ligand. Complexes 1 and 2 give rise to 3D metal-organic supramolecular frameworks having rectangular cavities formed via hydrogen bonding and pi-pi stacking interactions. The complexes were further characterized by elemental analysis, spectroscopic methods (IR, H-1 NMR and UV-vis), electrochemical study and thermogravimetric analysis. DFT calculations were used to study the electronic properties of the complexes.

• 出版日期2016-9-1