Dawson结构磷钨钒杂多酸有机铵盐的合成及光谱研究

以偏钒酸铵、磷酸二氢钠和钨酸钠为原料，调节溶液的pH值为4，控制反应时间为10 h，合成了三钒取代的Dawson结构磷钨钒杂多酸，然后以化学反应计量的5倍量加入抗衡离子K+,制备了母体杂多酸盐K9P2W15V3O62·41H2O。在不断的搅拌下，将母体杂多酸盐的酸性溶液缓慢滴加到十六烷基三甲基溴化铵溶液中，合成了目标化合物磷钨钒杂多酸有机铵盐(C19H42N)6H3[P2W15V3O62]。经元素分析、红外光谱、X射线粉末衍射、差热-热重等手段进行了表征，表明目标化合物仍保持Dawson结构，为未见文献报道的杂多化合物。

Synthesis and Spectral Study of Amine Salt of Tungstovanadophosphoric Heteropolyacid with Dawson Structure

Parent heteropoly salt was prepared by the method of stepwise addition of materials-stepwise acidification and distillation. Firstly,tungstovanadophosphoric heteropolyacid with tri-wanadium-substituted Dawson structure was synthesized with ammonium metavanadate,sodium dihydrogen phosphate and sodium tungstate as materials under the conditions of pH 4 and reaction time of 10 h. Secondly,parent heteropoly salt K9P2W15V3O62·41H2O was prepared by adding counterion K+ 5 times as much as determined by stoichiometric relation of reaction to the solution of tungstovanadophosphoric heteropolyacid. The acid solution of the parent heteropoly salt was slowly added to the solution of hexadecyltrimethylammonium bromide with continually stirring,then amine salt of tungstovanadophosphoric heteropolyacid,(C19H42N)6H3[P2W15V3O62] was synthesized. The target compound was characterized by elemental analysis,IR,XRD powder diffraction and TG-DTA,and the results indicated that it was a new heteropoly compound retaining Dawson structure.