An efficient synthesis of α-acyloxyacrylate esters as candidate monomers for bio-based polymers by heteropolyacid-catalyzed acylation of pyruvate esters
作者:Wataru Ninomiya、Masahiro Sadakane、Shinji Matsuoka、Hiroki Nakamura、Hiroyuki Naitou、Wataru Ueda
DOI:10.1039/b914515j
日期:——
A series of α-acyloxyacrylate esters are candidate monomers for bio-based polymers, converted from biomass feedstock. Polymers from these monomers are useful materials for bio-based plastics showing high heat resistance and transparency. In this paper, a new efficient method for α-acyloxyacrylate ester synthesis with a strong inorganic acid, heteropolyacid, is presented. The reaction in the presence of the heteropolyacid catalyst was carried out in liquid phase under mild conditions and showed higher productivity than that of the conventional synthesis with a typical organic acid, p-toluenesulfonic acid. Among the various heteropolyacids examined, α-Keggin-type tungsten-based phosphotungstic acid, H3PW12O40, showed the best performance, suggesting that the acid strength of the heteropolyacid is the crucial property for this reaction. We also found that pyruvate ester was consecutively converted into α-acyloxyacrylate estervia2,2-diacyloxypropionate ester.
一系列α-酰氧基丙烯酸酯是生物基聚合物的候选单体,这些单体由生物质原料转化而来。由这些单体聚合得到的聚合物是具有高耐热性和透明度的生物基塑料的有用材料。本文提出了一种新的高效方法,使用强无机酸——杂多酸来合成α-酰氧基丙烯酸酯。在杂多酸催化剂存在下,反应在液相温和条件下进行,其生产效率高于使用典型有机酸——对甲苯磺酸的传统合成方法。在所考察的多种杂多酸中,α-Keggin型钨基磷钨酸H3PW12O40表现最佳,这表明杂多酸的酸强度是该反应的关键特性。我们还发现,丙酮酸酯连续转化为α-酰氧基丙烯酸酯,是通过2,2-二酰氧基丙酸酯途径进行的。