Synthesis, properties and crystal structure of some polyoxometallates containing the tris(hydroxymethyl)aminomethane cation

摘要

Polyoxometallates [(CH2OH)(3)CNH3](3)PMo12O40. 5H(2)O, [(CH2OH)(3)CNH3](3)PW12O40. 11H(2)O, [(CH2OH)(3)CNH3](2)H2SiW12O40. 10H(2)O, [(CH2OH)(3)CNH3](4)GeW12O40. 9H(2)O, [C4H12NO3](4)SiMo12O40. 5H(2)O, [(CH2OH)(3)CNH3](2)H4P2W18O62. 3H(2)O and C(CH2-OH)(3)CNH3](3)H3As2W18O62. 4H(2)O have been synthesized for the first time, purified, and structurally characterized by means of elemental analyses, IR spectrum, electronic spectrum, cyclic voltammogram, P-31 NMR and X-ray diffraction. The crystal structure of [(CH2OH)(3)CNH3](4)PMo12O40. 5H(2)O has been determined by X-ray diffraction. Hydrogen bonding between (CH2OH)(3)CNH2 and PMo12O403- was Inferred from heavy atom distances. The solid reflectance electronic spectra and IR spectra indicate that there is interaction between the H3PMo12O40 and the organic substrate. The complexes have photosensitivity under irradiation of sunlight to result in charge transfer by oxidation of (CH2OH)(3)CNH2 and the reduction of the polyoxometallates. We also found that [(CH2OH)(3)CNH3](3)PMo12O40. 5H(2)O and [(CH2OH)(3)CNH3](3) PW12O40. 11H(2)O exhibited substantial catalytic activity toward the electro-reduction of bromate and nitrite, respectively. (C) 2000 Elsevier Science S.A. All rights reserved. [References: 56]