Two 3d–4f heterometallic monovacant Keggin phosphotungstate derivatives

Two 3d–4f heterometallic monovacant Keggin phosphotungstate derivatives [Cu(dap)(H2O)2]0.5[Cu(dap)2]4H2[Pr(α-PW11O39)2] · 3H2O (1) and [Cu(en)2(H2O)]2[Cu(en)2]1.5H4[Pr(α-PW11O39)2] · 10H2O (2) (dap = 1,2-diaminopropane, en = ethylenediamine) have been hydrothermally synthesized by reaction of the trivacant Keggin phosphotungstate precursor Na9[A-α-PW9O34] · 7H2O with CuCl2 · 2H2O and PrCl3 in the presence of dap or en and structurally characterized by elemental analyses, IR spectra, X-ray single-crystal diffraction, and thermogravimetric analyses. Compound 1 crystallizes in the triclinic space group P 1 with a = 17.325(3), b = 18.917(3), c = 19.938(3) Å, α = 104.481(2), β = 98.968(3), γ = 91.306(3)°, V = 6236.4(18) Å3, Z = 2, GOOF = 1.000, R 1 = 0.0806, wR 2 = 0.2016. Compound 2 also belongs to the triclinic space group P 1 with a = 16.005(4), b = 18.053(4), c = 21.127(5) Å, α = 113.894(3), β = 90.745(4), γ = 94.255(4)°, V = 5560(2) Å3, Z = 2, GOOF = 0.999, R 1 = 0.0686, wR 2 = 0.1885. Both 1 and 2 display organic–inorganic hybrid 2-D sheet architectures built by classic mono-PrIII sandwiched dimeric moieties [Pr(α-PW11O39)2]11− through [Cu(L)2]2+ bridges (L = dap, en), which represent rare organic–inorganic hybrid 2-D 3d–4f heterometallic monovacant Keggin polyoxometalates.