Controllable construction of isoquinolinedione and isocoumarin scaffolds <i>via</i> Rh<sup>III</sup>-catalyzed C–H annulation of <i>N</i>-tosylbenzamides with diazo compounds
An efficient protocol for the synthesis of isoquinolinediones by RhIII-catalyzed C–H activation/annulation/decarboxylation of N-tosylbenzamides with diazo compounds is reported.
Nonracemic ethano-bridged Tröger bases are prepared using CuTC-catalyzed decompositions of diazo compounds. Excellent levels of diastereo- and enantio-control (dr and ee up to 12 : 1 and 95% respectively) are now obtained with aryl diazoketone precursors.
promoting sp2 C-H bond insertion at the para position of unprotected phenols because of the exceptionally chemical reactivity of gold-stabilized carbophilic carbocations. Herein, we present a gold(i)-catalysed three-component reaction between phenols, diazocarbonyl compounds and allenamides, affording the corresponding three-component reaction products with excellent geometric selectivity (E : Z > 20 : 1)
Synthesis of Chiral Esters via Asymmetric Wolff Rearrangement Reaction
作者:Jing Meng、Wei-Wei Ding、Zhi-Yong Han
DOI:10.1021/acs.orglett.9b03227
日期:2019.12.20
The first asymmetric Wolff rearrangement reaction that directly converts α-diazoketones into broadly useful chiral α,α-disubstituted carboxylic esters with high enantioselectivities (up to 97.5:2.5 er) is reported. The cascade reaction proceeds through the seamless combination of visible-light-induced formation of the ketene intermediate and asymmetric ketene esterification using a readily available
Engineering Dirhodium Artificial Metalloenzymes for Diazo Coupling Cascade Reactions**
作者:David M. Upp、Rui Huang、Ying Li、Max J. Bultman、Benoit Roux、Jared C. Lewis
DOI:10.1002/anie.202107982
日期:2021.10.25
numerous protein and small molecule components required for the cascadereaction had minimal effect on ArM catalysis. Directedevolution of the ArM led to improved yields and E/Z selectivities for a variety of substrates, which translated to cascadereaction yields. MD simulations of ArM variants were used to understand the structural role of the cofactor on ArM conformational dynamics. These results
人工金属酶 (ArMs) 通常用于控制催化反应的立体选择性,但控制化学选择性仍然具有挑战性。在这项研究中,我们设计了一种 dirhodium ArM 来催化重氮交叉偶联形成烯烃,该烯烃在一锅级联反应中被烯烃还原酶还原为具有高对映选择性(通常 > 99% ee)的烷烃. 级联反应所需的大量蛋白质和小分子成分对 ArM 催化的影响很小。Arm 的定向进化提高了产量和E / Z对各种底物的选择性,这转化为级联反应产率。ArM 变体的 MD 模拟用于了解辅助因子对 ArM 构象动力学的结构作用。这些结果突出了 ArMs 控制催化剂立体选择性和化学选择性的能力,以实现在复杂介质中的反应,否则会导致不希望的副反应。