A New Route to 4-Ethynyl- N -hydroxy-2-imidazolidinones via Oxime Addition
摘要:
A rapid route was developed to afford ethynyl-substituted imidazole derivatives which served as key compounds for aryl-alkynyl-coupling reactions. Addition of mono-silylated acetylene to O-protected oximes was carried out in the absence of Lewis acids, directly affording the title compounds 3a-c in a one-pot reaction. Limitations and dependence of the feasibility on N-1-substituents are discussed. (C) 2000 Elsevier Science Ltd. All rights reserved.
Nucleophilic Aromatic Substitution of Unactivated Fluoroarenes Enabled by Organic Photoredox Catalysis
作者:Vincent A. Pistritto、Megan E. Schutzbach-Horton、David A. Nicewicz
DOI:10.1021/jacs.0c09296
日期:2020.10.7
use of organic photoredox catalysis renders this method operationally simple under mild conditions and is amenable to various nucleophile classes, including azoles, amines, and carboxylic acids. Select fluorinated heterocycles can be functionalized using this method. In addition, the late-stage functionalization of pharmaceuticals is also presented. Computational studies demonstrate that the site selectivity
Mechanistic Investigations into Amination of Unactivated Arenes via Cation Radical Accelerated Nucleophilic Aromatic Substitution
作者:Vincent A. Pistritto、Shubin Liu、David A. Nicewicz
DOI:10.1021/jacs.2c04577
日期:2022.8.24
A mechanistic investigation into the amination of electron-neutral and electron-rich arenes using organic photoredox catalysis is presented. Kinetic and computational data support rate-limiting nucleophilic addition into an arene cation radical using both azole and primary amine nucleophiles. This finding is consistent with both fluoride and alkoxide nucleofuges, supporting a unified mechanistic picture
提出了利用有机光氧化还原催化对电子中性芳烃和富电子芳烃进行胺化的机理研究。动力学和计算数据支持使用唑和伯胺亲核试剂对芳烃阳离子自由基进行限速亲核加成。这一发现与氟化物和醇盐离核剂一致,支持使用阳离子自由基加速亲核芳香取代(CRA-S N Ar)的统一机制图。电化学和时间分辨荧光光谱证实了溶剂在胺存在下选择性芳烃氧化中发挥的关键作用。通过光物理研究阐明了呫吨盐的合成局限性。提出了一种具有改善的周转数的替代催化剂支架。
Ultrasound assisted one-pot synthesis of benzo-fused indole-4,9-dinones from 1,4-naphthoquinone and α-aminoacetals
作者:Quang H. Luu、Jorge D. Guerra、Cecilio M. Castañeda、Manuel A. Martinez、Jong Saunders、Benjamin A. Garcia、Brenda V. Gonzales、Anushritha R. Aidunuthula、Shizue Mito
DOI:10.1016/j.tetlet.2016.04.031
日期:2016.5
A one-pot synthesis of benzo[f]indole-4,9-diones from 1,4-naphthoquinone with alpha-aminoacetals has been developed. This method provides a straightforward synthesis of benzo[f]indole-4,9-diones via intramolecular nucleophilic attack of aminoquinones to aldehydes under mild reaction conditions. The detailed mechanism was also investigated. (C) 2016 Elsevier Ltd. All rights reserved.
Access to Unsymmetrically Substituted Diaryl Gold N‐Acyclic Carbene (NAC) and N‐Heterocyclic Carbene (NHC) Complexes via the Isonitrile Route
作者:Vanessa Vethacke、Vanessa Claus、Martin C. Dietl、Daniel Ehjeij、Arne Meister、Jonas F. Huber、Leon K. Paschai Darian、Matthias Rudolph、Frank Rominger、A. Stephen K. Hashmi
DOI:10.1002/adsc.202101000
日期:2022.2
of unsymmetric diaryl gold N-acyclic carbene (NAC) complexes was synthesized via the isonitrile route by three different methods: (a) solvent free in a melt, (b) mechanochemically and (c) in THF at room temperature. The latter method can also be used to synthesize unsaturated gold NHC complexes. These methods overall offer access to a broad array of new complexes and remove one of the previous limitations
A rapid route was developed to afford ethynyl-substituted imidazole derivatives which served as key compounds for aryl-alkynyl-coupling reactions. Addition of mono-silylated acetylene to O-protected oximes was carried out in the absence of Lewis acids, directly affording the title compounds 3a-c in a one-pot reaction. Limitations and dependence of the feasibility on N-1-substituents are discussed. (C) 2000 Elsevier Science Ltd. All rights reserved.