Highly efficient usage of the hydrothermal technique through the one-pot method to construct four Keggin-based compounds containing pendent ligands

Abstract

By utilizing two kinds of pendent organic ligands, four new Keggin-based compounds, [Ag(bpz)2(pz)(H2O)(H3PMo12O40)2] (), [Ag(bpz)2(H3PMo12O40)]·2H2O (), [Ag(btz)4(PMo12O40)] () and [Ag(btz)3(PMo12O40)]·H2O () (bpz = 4-butyl-1H-pyrazole, pz = pyrazole, btz = 1-benzyl-1H-(1,2,4)triazole), were synthesized under hydrothermal conditions and characterized by single crystal X-ray diffraction. Compounds and were obtained in one-pot reaction, as well as compounds and . In compound , six Ag(I) ions are fused by four bpz and two pz molecules to form a hexa-nuclear cycle, with two coordinated water embedding through Ag-O bonds. The three-connected Mo13-containing PMo12 anions connect these cycles alternately to construct 1D chains, which are further linked by four-connected Mo1-containing PMo12 anions to build a 3D framework of . Compound contains 1D Ag(I) chains, linked by four-connected Mo1-containing PMo12 and two-connected Mo7-containing PMo12 respectively to construct a 3D structure. The pz ligand was not observed in . In compound , there exist [Ag(btz)4](3+) subunits, which are alternately connected by PMo12 anions to form a 1D chain. In compound , there exists a zigzag Ag-btz chain. The adjacent chains are further linked by Ag-C bonds and a 2D metal-organic layer is constructed. The PMo12 anions link adjacent layers to build a 3D framework of . The syntheses of compounds and , and prove that the one-pot method under hydrothermal conditions is efficient for pursuing even two more kinds of crystals.