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在有机合成中具有优良催化性能的杂多酸已被越来越多的人们所熟悉。钨硼酸则是其中研究最早的杂多酸之一。其制备方法已有多人从事过研究。最为人们熟知的是Copaux法:把钨酸钠溶液用盐酸酸化并和140倍于化学计量的硼酸个起煮沸。该方法的缺点是:1.要求硼酸极大过量;2.需要煮沸溶液若干小时并外加无机酸酸化溶液;3.得到的是两种钨硼酸(四
Heteropolyacids with excellent catalytic performance in organic synthesis have become familiar to more and more people. Tungstoboric acid is one of the earliest studied heteropoly acids. Many people have done research on its preparation method. The most well-known is the Copaux method: The sodium tungstate solution is acidified with hydrochloric acid and boiled over 140 times the stoichiometric amount of boric acid. The disadvantages of this method are: 1. Requires a very large excess of boric acid; 2. Requires boil solution for several hours plus an acid solution of inorganic acid; 3. Two tungstoboric acid (tetrakis