Evans-Showell-type polyoxometalate constructing novel 3D inorganic architectures with alkaline earth metal linkers: syntheses, structures and catalytic properties.

摘要: Four new architectures containing [Co2Mo10H4O38]6− polyoxoanions, (C2N2H10)2[Sr(H2O)5][Co2Mo10H4O38]·2H2O 1, (C2N2H10)2[Ba(H2O)3][Co2Mo10H4O38]·3H2O 2, (C3N2H12)2[Sr(H2O)5][Co2Mo10H4O38]·3H2O 3 and (C3N2H12)[Ba(H2O)4][Ba(H2O)4][Co2Mo10H4O38]·2H2O 4 (C2N2H10 = ethylenediamine; C3N2H12 1,3-propanediamine) have been synthesized characterized by elemental analysis, IR spectroscopy, solid diffuse reflective TG powder X-ray diffraction single crystal diffraction. Compounds 1 2 obtained in the presence of ethylenediamine, are made Evans–Showell-type anions [Co2Mo10H4O38]6−, linked Sr2+ or Ba2+ cations to form 3D frameworks. To our knowledge, compound 1(2) represents first example architecture which Evans–Showell were pure alkaline earth cations. When propanediamine was used instead compounds with 2D networks obtained. This phenomenon indicates that organic cations, adjust reaction pH values, can induce different dimensional inorganic As heterogeneous catalysts, 1–4 show excellent catalytic performance cyanosilylation carbonyl compounds. Furthermore, these reactions performed under solvent-free conditions using only a low amount catalysts be recovered reused without displaying any significant loss activity. far as we know, represent examples catalyzed POM-based species metal