高单酯含量的甲基丙烯酸-β-羟乙酯磷酸酯的催化合成

Catalytic Selective Synthesis of Mono(2-Methacryloyloxyethyl) Phosphate

采用浸渍法将磷钨酸及其盐[TEAH]3PW12O40负载到活性炭上制备出HPW/AC和TEAPW/AC 2个系列的催化剂,并用IR、XRD、N2-吸附脱附和NH3-TPD等技术手段对它们的结构和酸性进行了表征。进一步,以P2O5为磷酸化剂考察了上述催化剂在功能性磷酸酯—甲基丙烯酸-β-羟乙酯磷酸酯合成中的催化性能。结果显示,上述催化剂在该酯化反应中不仅具有很高的活性,而且由于催化剂的微孔结构抑制了双、三酯的生成,明显提高了单酯的选择性。在优化的反应条件和催化剂上,酯化率可达94%,单酯选择性可达95%。且催化剂高度稳定,可以重复使用。该催化剂和催化工艺不仅克服了磷酸酯合成中使用含氯原料的缺点,而且大大提高了产物中单酯的含量。

Two series of catalysts, HPW/AC and TEAPW/AC, were prepared by impregnating tungstophosphoric acid and [ TEAH]3PW12O40 solution on active carbon. The structure and acidic property of these catalysts were characterized by IR, XRD, N2 adsorption-desorption and NH3-TPD techniques. Then these catalysts were used to catalyze the synthesis of 2-methacryloyloxyethyl phosphate, a functional phosphate, by using P2O5 as phosphorylation agent. These catalysts possess not only high activity but also high selectivity for the mono （2-methacryloyloxyethyl） phosphate since the formations of di （2-methacryloyloxyethyl） phosphate and tri （2-methacryloyloxyethyl） phosphate are restricted by the micropores of catalysts. Under the optimum conditions and on the optimal catalyst, the total ester yield and the selectivity of mono （2- methacryloyloxyethyl） phosphate are 94% and 95%, respectively. The catalyst can be isolated and recycled with high stability. This catalytic process not only avoids using chlorine-containing reagent in the synthesis, but also greatly increases monophoshpate content in the product.