A Rh(III)-catalyzed one-pot reaction of N-phenoxyacetamides, ketones, and hydrazines for a facile access to disubstituted and trisubstituted ethylenes is reported. In this method, various ketones are transformed into donor–donor diazo compounds, which engage in insertion with N-phenoxyacetamides, following β-H elimination under Rh(III) catalysis to generate (E)-polyaryl-substituted olefins. This chemistry
Photocatalyzed Intramolecular [2+2] Cycloaddition of
<i>N</i>
‐Alkyl‐
<i>N‐(</i>
2‐(1‐arylvinyl)aryl)cinnamamides
作者:Wanderson C. Souza、Bianca T. Matsuo、Priscilla M. Matos、José Tiago M. Correia、Marilia S. Santos、Burkhard König、Marcio W. Paixão
DOI:10.1002/chem.202003641
日期:2021.2.19
N‐Alkyl‐N‐(2‐(1‐arylvinyl)aryl)cinnamamides are converted into natural product inspired scaffolds via iridium photocatalyzed intramolecular [2+2] photocycloaddition. The protocol has a broad substrate scope, whilst operating under mild reaction conditions. Tethering four components forming a trisubstituted cyclobutane core builds rapidly high molecular complexity. Our approach allows the design and
N-烷基-N-( 2-(1-芳基乙烯基)芳基)肉桂酰胺通过铱光催化的分子内[2 + 2]光环加成反应转变为天然产物。该协议具有广泛的底物范围,同时在温和的反应条件下运行。束缚形成三取代的环丁烷核心的四个成分会迅速建立高分子复杂性。我们的方法允许设计和合成多种四氢环丁酮[ c ]喹啉-3(1 H)-酮,产率在20–99%之间,并且具有出色的区域选择性和非对映选择性。此外,已证明在环丁烷环断裂后,1,7-烯炔的分子内[2 + 2]-环加成反应会导致类似烯炔的复分解。
Lewis Acid Catalyzed Cyclization of Propargylic Alcohols with 2-Vinylphenol
An unprecedented Lewis acidcatalyzed, protection-free, and high-efficiency synthesis of valuable 3,4-dihydro-2H-2,4-methanochromans via cycloaddition of propargylic alkynols with 2-vinylphenol is described. This cycloaddition protocol, which tolerates a wide variety of functional groups, provides practical, versatile, and atom-economical access to a new class of appealing bridged-ring products in
本文描述了一种空前的路易斯酸,其通过炔丙基炔醇与2-乙烯基苯酚的环加成反应,催化了有价值的3,4-二氢-2 H -2,4-甲烷二甲基苯并没有保护性地进行了高效合成。该环加成方案可耐受多种官能团,以令人满意的收率提供实用,通用且经济实惠的途径来获得新型的有吸引力的桥环产品。与报道的桥环骨架合成反应条件相比,目前的反应条件是中性,温和且没有任何添加剂。
Intermolecular Photocatalyzed Heck-like Coupling of Unactivated Alkyl Bromides by a Dinuclear Gold Complex
作者:Jin Xie、Jian Li、Vanessa Weingand、Matthias Rudolph、A. Stephen K. Hashmi
DOI:10.1002/chem.201602939
日期:2016.8.26
A practical protocol for a photocatalyzed alkyl‐Heck‐like reaction of unactivated alkyl bromides and different alkenes promoted by dinuclear gold photoredox catalysis in the presence of an inorganic base is reported. Primary, secondary, and tertiary unactivated alkyl bromides with β‐hydrogen can be applied. Esters, aldehydes, ketones, nitriles, alcohols, heterocycles, alkynes, alkenes, ethers, and
Rhodium(III)-Catalyzed<i>ortho</i>Alkenylation of<i>N</i>-Phenoxyacetamides with<i>N</i>-Tosylhydrazones or Diazoesters through CH Activation
作者:Fangdong Hu、Ying Xia、Fei Ye、Zhenxing Liu、Chen Ma、Yan Zhang、Jianbo Wang
DOI:10.1002/anie.201309650
日期:2014.1.27
A coupling reaction of N‐phenoxyacetamides with N‐tosylhydrazones or diazoestersthrough RhIII‐catalyzed CHactivation is reported. In this reaction, ortho‐alkenyl phenols were obtained in good yields and with excellent regio‐ and stereoselectivity. Rh–carbene migratory insertion is proposed as the key step in the reaction mechanism.