Two 1,3-bis[tris(hydroxymethyl)methylamino]propane functionalized 3d–4f heterometallic arsenotungstates

Abstract

Two novel 1,3-bis[tris(hydroxymethyl)methylamino]propane (H6L) functionalized 3d-4f heterometallic arsenotungstates (ATs) [H2N(CH3)2]5Na2H4[Cu(H2L)]{[Ln0.5Na1.5Cu3(H2O)5](AsW9O33)2}·17H2O [Ln = HoIII (1), YbIII (2)] have been synthesized in conventional aqueous solution by using simple materials and further characterized by elemental analyses, IR spectra, thermogravimetric analyses, powder X-ray diffraction spectra and single-crystal X-ray diffraction. The most prominent structural feature of 1 and 2 is that two trivacant Keggin [B-α-AsW9O33]9− subunits sandwich an opening pentagonal metallocycle heterometallic cluster [Cu(H2L)Ln0.5Na1.5Cu3(H2O)5]7+ with the copper-organic group [Cu(H2L)]2−. The UV absorption spectra illustrate that 1 is stable in the pH range of 2.48–8.02. The solid-state electrochemical properties of 1 have also been measured in 0.5 mol·L−1 H2SO4/Na2SO4 aqueous solution by entrapping it in a glass carbon electrode. Furthermore, the variable-temperature magnetic susceptibility of 1 shows the weak CuII − HoIII ferromagnetic interactions.