Enantioselective Synthesis of Cyclopentene Carbaldehydes by a Direct Multicatalytic Cascade Sequence: Carbocyclization of Aldehydes with Alkynes
作者:Kim L. Jensen、Patrick T. Franke、Carlos Arróniz、Sara Kobbelgaard、Karl Anker Jørgensen
DOI:10.1002/chem.200903405
日期:2010.2.8
A multicatalytic, asymmetric cascade reaction sequence of α,β‐unsaturated aldehydes with alkyne‐tethered nucleophiles has been developed. Organocatalytic iminium–enamine catalysis combined with Lewis acid alkyne activation gave cyclopentenecarbaldehyde products in good yields and excellent stereoselectivities (see scheme). To highlight the potential of the sequence, a key structure for the preparation
porous palladium(II)‐polyimines are excellent catalysts for cooperatively catalyzed and enantioselective cascadereactions. In synergy with a chiral amine co‐catalyst, polysubstituted cyclopentenes and spirocyclic oxindoles, including the all‐carbon quaternary stereocenter, were synthesized in high yields. High diastereo‐ and enantioselectivities were achieved for these dynamic kinetic asymmetric transformations
The first examples of one‐pot highly chemo‐ and enantioselectivedynamickineticasymmetrictransformations (DYKATs) involving α,β‐unsaturated aldehydes and propargylated carbon acids are presented. These DYKATs, which proceed by a combination of catalytic iminium activation, enamine activation, and Pd0‐catalyzed enyne cycloisomerization, give access to functionalized cyclopentenes with up to 99 % ee
Copper(I)-Catalyzed Dearomative (3 + 2) Cycloaddition of 3-Nitroindoles with Propargylic Nucleophiles: An Access to Cyclopenta[<i>b</i>]indolines
作者:Johanne Ling、David Mara、Baptiste Roure、Maxime Laugeois、Maxime R. Vitale
DOI:10.1021/acs.joc.9b03459
日期:2020.3.6
The copper(I)-catalyzed dearomatization of 3-nitroindoles with propargylic nucleophiles is described. In mild reaction conditions, this original dearomative (3 + 2) cycloaddition process gives access to a wide variety of cyclopenta[b]indolines in good to excellent yields, with high functional group tolerance. The proof of concept that an enantioselective version of this reaction is accessible by employing
作者:Luca Deiana、Yan Jiang、Carlos Palo-Nieto、Samson Afewerki、Celia A. Incerti-Pradillos、Oscar Verho、Cheuk-Wai Tai、Eric V. Johnston、Armando Córdova
DOI:10.1002/anie.201310216
日期:2014.3.24
Herein is described a versatile and broad synergistic strategy for expansion of chemical space and the synthesis of valuable molecules (e.g. carbocycles and heterocycles), with up to three quaternary stereocenters, in a highly enantioselective fashion from simple alcohols (31 examples, 95:5 to >99.5:0.5 e.r.) using integrated heterogeneousmetal/chiralaminemultiplerelaycatalysis and air/O2 as the terminal
本文描述了一种通用的,广泛的协同策略,用于扩展化学空间和合成有价值的分子(例如碳环和杂环),并具有多达三个四级立体中心,以对映体的方式从简单的醇类中高度选择性(31例,95:5至> 99.5:0.5 er),使用集成的多相金属/手性胺多重中继催化,并将air / O 2用作末端氧化剂。一种新型的高度1,4-选择性多相金属/胺共催化的烯醛加氢反应也被添加到中继催化序列中。