Study On Catalysis Of Heteropoly Acid In Fine Organic Synthesis

Since heteropoly acid was applied successfully in industrialization of propylene hydration in 70 s in Japan, as a new type of catalyst used in organic synthesis and petroleum chemical combination, heteropoly acid is interesting with the characterization of special acidity, pseudoliquid phase and many functions.hi this article, four kinds of heteropoly acid catalysts were prepared ( H3PW₁₂O₄₀/C H₄PMo₁₁O40 H₅PMo₁₀V₂O₄₀ and H₆PMo₉V3O₄₀).They were applied in synthesis of acetals and ketals from pentaerythritol with carbonyl compounds, synthesis of alkyl bromides from alcohols and prepration of anthraquinone from liquid-phase oxidation of anthracene.the catalysis effect is very good.A. The acid catalysis reaction of HPA (1) The acetals and ketals reactions of pentaerythritolSynthesis of twelve kind of ketals and acetals from 2,2- bis (hydroxymethyl)propane-l,3-diol with aldehydes and ketones were catalysed by phosphotungstic acid supported on active carbon (HPW/C),and a new compound has been produced, the factors influencing yield were investigated. It is show that HPW/C is an excellent catalyst, and the catalyst was stabtilitive and reusable. The products were characterized by 1HNMR, IR and elemental analysis.Synthesis of diketals and diacetals form 2,2-bis (hydroxymethyl) -propane- 1,3-diol with aldehydes and ketones were catalyzed by phosphotungstic acid supported on active carbon under microwaveirradiation, under the optimum reaction conditions(Pentaerythritol 2.0g, HPW/C 0.3g, cyclohexanone 4.0ml, microwave power 600W, microwave irradiation time 3min),the yield of diketal was 95.4%. under microwave irradiation ,the reaction rate was 30 times faster than conventional heating.The products were characterized by 'HNMR, IR and elemental analysis. (2) The bromization reaction of dodecyl alcohol1 -bromododecane was prepared on the basis of dodecyl alcohol and hydrobromic acid by phosphotungstic acid supported on active carbon(HPW/C), the factors influencing the yield were investigated, the suitable preparation conditions of 1-bromododecane were determined: reaction temperaturell0 ,reaction time 6h, mole ratio n(Ci2H25 OH) :n(HBr)=l.0:2.0, amount of catalyst m(C₁₂2H25OH):m(cat)=10:l, The yield of 1-bromododecane was 91.8%.B: The oxidation catalysis of heteropoly acidsThe molybdovanadophoric heteropoly acids with Keggin structure were synthesized. IR and XRD were used to evidence the structure of the catalysts.catalysting the reaction of anthracene with H₂O₂ was studied.the influence of temperature ,reaction time ,catalyst amount .solvent on catalytic activity was examined . The yield of anthraquinone was over 90% under the optimum conditions .The method of preparing anthraquinone was good because of its simplicity, mild conditions and high catalytic activity and thereby was prospective in industrial application .The author has made more comprehesive review on heteropoly acid catalysts'structure,capability and their application at catalysis synthesis.