三维碳硼烷衍生物的内在手性是通过二十面体笼上的取代模式建立的,与有机合成中观察到的平面、轴向、中心和螺旋手性相比,其研究要少得多。基于过渡金属催化的不对称B-H活化方法,添加官能团可以将对称的邻碳硼烷转变为手性笼结构。在此,我们报道了3-酰氨基-邻碳硼烷与二芳基乙炔的不对称硼顶点烯基化,以开发邻碳硼烷的笼( S )-B(4)/( R )-B(7)对映选择性。在温和的反应条件下,Ir 催化剂促进的不对称 ( S )-B(4)-H 活化可实现高达 99% ee 的高效率。对映控制模型是根据 DFT 结果提出的,其中手性膦配体在邻碳硼烷的催化对映选择性 B-H 活化中起着至关重要的作用。
A new porousorganicpolymer supported rhodium catalyst (Rh/POL-BINAPa&PPh3) has been developed for the hydroformylation of various alkynes to afford the corresponding α,β-unsaturated aldehydes with high chem- and stereoselectivity, excellent catalytic activity and good reusability (10 cycles). The heterogeneouscatalyst exhibited more catalytic activity than the comparable homogeneous Rh/BINAPa/PPh3
Thermolysis of Sodium Salts of Tosylhydrazones of Some Heterocyclic Aldehydes in the Presence of Silver Chromate: 1,3 NŮC Migration of Tosyl Group
作者:Katsuhiro Saito、Hiraku Ishihara
DOI:10.3987/r-1987-07-1891
日期:——
Enantioselective Alkenylation of <i>o</i>-Carboranes via Ir-Catalyzed Asymmetric B–H Activation
作者:Huifang Zhang、Jie Zhang、Zaozao Qiu、Zuowei Xie
DOI:10.1021/acscatal.3c03997
日期:2023.11.3
The intrinsic chirality of three-dimensional carborane derivatives is established by the substitution patterns on the icosahedral cage, which is much less studied than the planar, axial, central, and helical chirality observed in organic synthesis. Based on transition-metal-catalyzed asymmetrical B–H activation methodology, the addition of functional groups can change the symmetrical o-carborane to
三维碳硼烷衍生物的内在手性是通过二十面体笼上的取代模式建立的,与有机合成中观察到的平面、轴向、中心和螺旋手性相比,其研究要少得多。基于过渡金属催化的不对称B-H活化方法,添加官能团可以将对称的邻碳硼烷转变为手性笼结构。在此,我们报道了3-酰氨基-邻碳硼烷与二芳基乙炔的不对称硼顶点烯基化,以开发邻碳硼烷的笼( S )-B(4)/( R )-B(7)对映选择性。在温和的反应条件下,Ir 催化剂促进的不对称 ( S )-B(4)-H 活化可实现高达 99% ee 的高效率。对映控制模型是根据 DFT 结果提出的,其中手性膦配体在邻碳硼烷的催化对映选择性 B-H 活化中起着至关重要的作用。