Inorganic Chemistry, Vol.59, No.7, 4985-4994, 2020
Efficient Catalytic Oxidative Desulfurization toward Thioether and Sulfur Mustard Stimulant by Polyoxomolybdate-Resorcin[4]arene-Based Metal-Organic Materials
The design and synthesis of effective and recyclable oxidative desulfurization catalysts is of great importance in view of environmental protection and human health. Herein, a family of polyoxomolybdate-based inorganic-organic hybrid materials, namely, [Mn(TMR4A)(H2O)(4)]-[Mo6O19]center dot 0.5CH(3)CH(2)OH center dot H2O (1), [Ni(TMR4A)(H2O)(4)]-[Mo6O19]center dot 0.5CH(3)CH(2)OH center dot H2O (2), [Zn(TMR4A)(H2O)(4)] [Mo6O19]center dot 0.5CH(3)CH(2)OH center dot H2O (3), and [Co-2(TMR4A)(2)(H2O)(4)(beta-Mo8O26)]center dot CH3CN center dot 12H(2)O (4), were assembled by the functionalized resorcin[4]arene ligand (TMR4A) with polyoxomolybdate and metal ions under solvothermal conditions. In isostructural 1-3, the [M(TMR4A)(H2O)(4)](2+) species (M = Mn-II, Ni-II, Zn-II) and [Mo6O19](2-) anions are held together via C-H center dot center dot center dot O hydrogen bonds to give a 3D supramolecular architecture. In 4, two [Co(TMR4A)(H2O)(2)](2+) cations were linked by one [beta-Mo8O26](4-) anion to produce an attractive molecular dimer. Remarkably, 1-4, as recyclable heterogeneous catalysts, exhibit efficient catalytic oxidation desulfurization activities toward thioethers. Particularly, 1, as a representative example, features selective catalytic oxidation for sulfur mustard simulant. Moreover, their electrochemical properties were also studied.