【作者】 吴华；

【导师】 龚流柱；

【作者基本信息】 中国科学技术大学 ， 有机化学， 2014， 博士

【摘要】 在众多的有机转化反应中,有机小分子催化剂与过渡金属所组成的联合催化体系已经成为一种极为重要和高效的合成方法。该类反应突破了以往单一催化体系的局限性,实现了由简单易得的起始原料,通过一步反应直接合成出结构复杂的目标分子。手性布朗斯特酸和过渡金属催化剂具有很好的兼容性,为协同以及接力催化模式的发展提高了广阔的空间。其中以BINOL骨架为基础所衍生出的一系列手性磷酸催化剂不仅能够活化底物,而且还往往能够与一些过渡金属如金、钯、钌等原位生成具有更高活性的金属磷酸盐,通过这种灵活多变的活化形式促进反应的立体选择性控制。我们通过一价金配合物和手性磷酸接力催化的方式,由简单易得的原料水杨醛、芳香炔醇、芳香胺出发,在温和的反应条件下一步合成出了结构复杂的具有光学活性的手性芳香螺环缩酮类化合物。该反应具有很好的立体选择控制结果,为螺环缩酮类化合物的不对称合成提供了重要借鉴。双组份催化剂体系已经研究的相对较多,然而多组分催化体系却很少被研究。我们运用金配合物/钯配合物/磷酸所组成的三分组催化剂体系,通过接力催化与协同催化共存的方式高效的合成了手性吡咯烷类化合物。在此反应中,一价金络合物首先催化第一步的关环反应,生成的反应烯胺中间体在零价钯和磷酸的协同催化下进行烯丙基化反应。此外,我们还对高价钯和手性磷酸所组成的催化体系进行了研究,派生出了有机高价碘催化的不对称C-H键官能化反应。该反应从简单的二芳香酰胺化合物出发,通过手性有机高价碘催化氧化,四个C-H键被同时立体选择性活化,最终实现了手性螺环氧化吲哚类化合物的不对称催化合成。更多还原

【Abstract】 Transition metal catalysis combined with organocatalysis has been shown to be an efficient asymmetric synthetic methodology. Various limitations of the traditional single catalyst system for asymmetric catalytic reactions were completely broken through by this robust catalytic method. A wide range of structurally diverse optically active products could be directly synthesized by employing simple and available substrates under the catalysis of transition metal/organocatalyst dual catalyst system in only one step. Chiral Br(?)nsted acids, especially chiral phosphoric acids derived from BINOL, have been demonstrated to be privileged catalysts enabling a diverse range of enantioselective transformations. More recently, the combination of Bronsted acids and transition metal complexes has emerged as a powerful tool in organic chemistry today.An asymmetric relay catalytic multicomponent reaction by using gold(Ⅰ) complex/chiral phosphoric acid was disclosed, which is able to assemble the readily available and easily accessible substrates into enantioenriched aromatic spiroacetals. The method provided an important alternative of known methods to directly access highly enantioenriched spiroacetals and would be potentially applied to the synthesis of spiroacetal motifs presented in natural products.Moreover, we have demonstrated a combination of the relay and cooperative catalysis with palladium/gold/phosphoric acid ternary system providing an unprecedented entry to pyrrolidine derivatives in high yields. In this cascade reaction, the gold complex serves a catalyst responsible for the hydroamination while palladium and Br(?)nsted acid cooperatively catalyze the allylic alkylation.Additionally, during the investigation of Pd(Ⅱ)/chiral phosphoric acid dual catalysts system, an asymmetric organocatalytic direct C-H/C-H oxidative coupling reaction of N1,N3-diphenylmalonamides was well established by using chiral organoiodine compounds as catalysts, wherein four C-H bonds were stereoselectively functionalized to give structurally diverse spirooxindoles with high levels of enantioselectivity.更多还原