Effect of Na(I)-H2O clusters on self-assembly of sandwich-type U(VI)-containing silicotungstates and the efficient catalytic activity for the synthesis of substituted phenylsulfonyl-1H-pyrazoles

In this study, a sandwich-type uranium(VI)-containing silicotungstate KNa11H2(H2O)30[Na(UO2)(SiW9O34)]2·8H2O (1) with new three-dimensional (3D) structure was synthesized and characterized using single-crystal X-ray diffraction, Fourier transform infrared, Raman, solid-state ultraviolet–visible diffuse reflection spectra, thermogravimetric analysis and powder X-ray diffraction. Single crystal analysis revealed that the Na(I)-H2O clusters in 1 showed a two-dimensional structure similar to (4,4)-network and resulted in the formation of a new 3D structure of 1. In addition, it was notable that 1 presented excellent catalytic activity for the synthesis of substituted phenylsulfonyl-1H-pyrazoles via the cyclization reaction of 1,3-diketones with various substituted benzenesulfonyl hydrazides.