Phosphomolybdic and phosphotungstic acids as efficient catalysts for the synthesis of bridged 1,2,4,5-tetraoxanes from β-diketones and hydrogen peroxide
作者:Alexander O. Terent'ev、Ivan A. Yaremenko、Vera A. Vil’、Igor K. Moiseev、Sergey A. Kon'kov、Valery M. Dembitsky、Dmitri O. Levitsky、Gennady I. Nikishin
DOI:10.1039/c3ob27239g
日期:——
Phosphomolybdic acid (PMA) and phosphotungstic acid (PTA) efficiently catalyze the addition of H2O2 to β-diketones to form bridged 1,2,4,5-tetraoxanes. These reactions are not accompanied by the formation of monocyclic peroxides containing hydroxy and hydroperoxide groups or polymeric peroxides. The use of these catalysts made it possible to obtain bridged tetraoxanes from easily oxidizable benzoylacetone derivatives and α-unsubstituted β-diketones. The syntheses are scaled up to ten grams. The resulting peroxides can be easily isolated from the reaction mixture by column chromatography. The yield of tetraoxanes depends on the structure of β-diketone and varies from 12 to 83%. NMR monitoring of two bridged 1,2,4,5-tetraoxanes synthesis was carried out.
磷钼酸(PMA)和磷钨酸(PTA)能有效地催化 H2O2 与 δ-二酮的加成反应,形成桥接的 1,2,4,5- 四氧杂环己烷。这些反应不会形成含有羟基和过氧化氢基团的单环过氧化物或聚合过氧化物。使用这些催化剂可以从易于氧化的苯甲酰丙酮衍生物和 δ- 未取代的 δ² 二酮中获得桥接四氧杂环己烷。合成量可放大到十克。由此产生的过氧化物可以很容易地通过柱层析从反应混合物中分离出来。四氧杂环己烷的产率取决于 β-二酮的结构,从 12% 到 83% 不等。对两个桥接的 1,2,4,5 四氧杂环己烷的合成进行了核磁共振监测。