论文部分内容阅读
以金鸡纳碱衍生物作为手性修饰剂,研究了三苯基膦稳定的Ir/SiO2催化剂催化芳香酮多相不对称加氢.通过电感耦合等离子体原子发射发谱(ICP-AES)、高分辨透射电镜(HRTEM)、X射线光电子能谱(XPS)、Brunauer-Emmett-Teller(BET)比表面积测试等固体表面分析手段对负载铱催化体系进行了表征;利用红外(IR)光谱、固体核磁共振(NMR)等分析手段初步表征了负载铱多相催化体系中手性修饰剂-金属-稳定剂在载体上的相互作用;利用“均相与多相催化体系的对比”、“催化剂稳定性实验”、“汞中毒实验”等方法阐明了手性修饰的负载铱催化体系是多相催化体系.还考察了稳定剂种类、修饰剂种类、金属负载量、溶剂、碱添加剂种类等因素对不对称加氢反应的影响.结果表明,金鸡纳碱衍生物对Ir/SiO2催化剂具有较好的修饰作用,在优化反应条件下苯乙酮及其衍生物加氢反应的对映选择性为52%-96%,4-乙酰基吡啶、2-乙酰基噻吩及2-乙酰基呋喃加氢反应的对映选择性可分别达到74%、75%及63%.
Using cinchona derivatives as chiral modifiers, we studied the multiphase asymmetric hydrogenation of aromatic ketones catalyzed by triphenylphosphine-stabilized Ir / SiO2 catalyst. ICP-AES, The supported Iridium catalytic system was characterized by HRTEM, XPS, Brunauer-Emmett-Teller (BET) surface area measurement. The IR spectra, Resonance (NMR) was used to characterize the interaction of the chiral modifier-metal-stabilizer on the support in iridium-supported heterogeneous catalytic system. By using the comparison of homogeneous and heterogeneous catalytic systems, Catalytic stability experiments “,” Mercury poisoning experiment "and other methods to clarify the chiral modification of the supported iridium catalytic system is a heterogeneous catalytic system also investigated the type of stabilizer, modifier species, metal loading, solvent, alkali The types of additives and other factors on the asymmetric hydrogenation reaction.The results show that the cinchona derivatives have a good modification of the Ir / SiO2 catalyst, under the optimal reaction conditions acetophenone and its derivatives hydrogenation reaction Selective Is 52% -96%. The enantioselectivities of 4-acetylpyridine, 2-acetylthiophene and 2-acetyl furan can reach 74%, 75% and 63%, respectively.