N-Heterocyclic Carbene-Catalyzed δ-Carbon LUMO Activation of Unsaturated Aldehydes
摘要:
An N-heterocyclic carbene (NHC) catalyzed domino reaction triggered by a delta-LUMO activation of alpha,beta-gamma,delta-diunsaturated enal has been developed for the formal [4 + 2] construction of multisubstituted arenes and 3-ylidenephthalide. These two products, formed in a highly chemo- and regioselective manner, were obtained via different catalytic pathways due to a simple change of the substrate. The activation of the remote delta-carbon of unsaturated aldehydes expands the synthetic potentials of NHC organocatalysis.
Construction of Multi-Substituted Benzenes via NHC-Catalyzed Reactions of Carboxylic Esters
作者:Jichang Wu、Chengli Mou、Yonggui Robin Chi
DOI:10.1002/cjoc.201700773
日期:2018.4
A carbene‐catalyzed ester activation reaction for the synthesis of multi‐substituted benzenes is developed. Tetra‐substituted benzene compounds are efficiently synthesized through this methodology. Compared with aldehyde substrates used in previous reports, the ester substrates used here are much more readily available and inexpensive. In addition, the TEMPO oxidant used here is more inexpensive than
[EN] METHOD OF FORMING A MULTI-SUBSTITUTED BENZENE COMPOUND<br/>[FR] MÉTHODE DE FORMATION D'UN COMPOSÉ BENZÈNE MULTI-SUBSTITUÉ
申请人:UNIV NANYANG TECH
公开号:WO2016013976A1
公开(公告)日:2016-01-28
The invention relates to a method of forming a multi-substituted benzene compound. In particular, the method involves benzene construction via organocatalytic formal [3+3] cycloaddition reaction.
Redox Active N-Heterocyclic Carbenes in Oxidative NHC Catalysis
作者:Sara Bacaicoa、Simon Stenkvist、Henrik Sundén
DOI:10.1021/acs.orglett.4c00731
日期:2024.4.19
An N-heterocycliccarbene (NHC) covalently linked to a quinone introduces a novel avenue for internal oxidations within oxidative NHC catalysis. The deployment of this hybrid NHC class promotes intramolecular electronic flow in the oxidation of the Breslow intermediate to acyl azolium. The use of the redox active NHC as a catalyst is facilitated by employing aerobic regeneration, yielding carboxylic
N-Heterocyclic Carbene-Catalyzed δ-Carbon LUMO Activation of Unsaturated Aldehydes
作者:Tingshun Zhu、Chengli Mou、Baosheng Li、Marie Smetankova、Bao-An Song、Yonggui Robin Chi
DOI:10.1021/jacs.5b02219
日期:2015.5.6
An N-heterocyclic carbene (NHC) catalyzed domino reaction triggered by a delta-LUMO activation of alpha,beta-gamma,delta-diunsaturated enal has been developed for the formal [4 + 2] construction of multisubstituted arenes and 3-ylidenephthalide. These two products, formed in a highly chemo- and regioselective manner, were obtained via different catalytic pathways due to a simple change of the substrate. The activation of the remote delta-carbon of unsaturated aldehydes expands the synthetic potentials of NHC organocatalysis.
Aerobic Oxidative N-Heterocyclic Carbene-Catalyzed Formal [3+3] Cyclization for the Synthesis of Tetrasubstituted Benzene Derivatives
作者:Sara Bacaicoa、Ellymay Goossens、Henrik Sundén
DOI:10.1021/acs.orglett.2c03879
日期:2022.12.16
Herein, we present an accessible aerobic N-heterocyclic carbene (NHC)-catalyzed method that efficiently produces tetrasubstituted benzene rings in a single reaction. The method employs atmospheric oxygen (O2) as the terminal oxidant in a reaction that requires two oxidative steps. The aerobic oxidation is achieved by a selection of electron transfer mediators orchestrating a redox cascade, turning
在此,我们提出了一种可获得的好氧 N-杂环卡宾 (NHC) 催化方法,该方法可在单个反应中有效地产生四取代苯环。该方法在需要两个氧化步骤的反应中使用大气中的氧气 (O 2 ) 作为末端氧化剂。有氧氧化是通过选择协调氧化还原级联的电子转移介质实现的,将高能有氧氧化反应途径转变为有利的过程。