Temperature-Dependent Immobilization of a Tungsten Peroxo Complex That Catalyzes the Hydroxymethoxylation of Olefins
作者:Jizhong Chen、Li Hua、Chen Chen、Li Guo、Ran Zhang、Angjun Chen、Yuhe Xiu、Xuerui Liu、Zhenshan Hou
DOI:10.1002/cplu.201402456
日期:2015.6
immobilization of tungsten peroxo complex was highly temperature-dependent. The tungsten peroxo complex can dissociate and diffuse into the liquid phase at reaction temperature, resulting in a homogeneous reaction. Nevertheless, the catalytically active species was anchored on the imidazole-functionalized silica by hydrogen bonding as the temperature was lowered to 0 °C after the reaction, which thus offered a
合成了由二齿吡啶甲酸配体稳定的过氧钨配合物,然后成功地将其固定在咪唑官能化的二氧化硅上。固定化的钨基催化剂被用作由烯烃和甲醇与H2 O2一锅合成β-烷氧基醇的有效催化剂。关于催化剂评估和通过各种方法表征的结果,证明了过氧化钨配合物的固定化高度依赖于温度。过氧化钨络合物可以在反应温度下解离并扩散到液相中,从而导致均相反应。然而,随着反应后温度降低至0°C,催化活性物质通过氢键键合固定在咪唑官能化的二氧化硅上,因此,它提供了一种高效的方法来使催化剂连续循环使用。另外,在相对温和的条件下,H 2 O 2可将各种烯烃以良好的转化率和选择性转化为相应的β-烷氧基醇。