Additive- and Photocatalyst-Free Borylation of Arylazo Sulfones under Visible Light
作者:Yuliang Xu、Xinying Yang、Hao Fang
DOI:10.1021/acs.joc.8b01662
日期:2018.10.19
developed a photocatalyst-free and additive-free, visible light induced borylation reaction using arylazo sulfones as starting material. This protocol shows some advantages such as mild conditions, simple equipment, and wide substrate scope, which gives a complementary protocol for the preparation of arylboronates.
Chan–Evans–Lam Amination of Boronic Acid Pinacol (BPin) Esters: Overcoming the Aryl Amine Problem
作者:Julien C. Vantourout、Robert P. Law、Albert Isidro-Llobet、Stephen J. Atkinson、Allan J. B. Watson
DOI:10.1021/acs.joc.6b00466
日期:2016.5.6
The Chan–Evans–Lam reaction is a valuable C–N bond forming process. However, aryl boronic acidpinacol (BPin) ester reagents can be difficult coupling partners that often deliver low yields, in particular in reactions with aryl amines. Herein, we report effective reaction conditions for the Chan–Evans–Lam amination of aryl BPin with alkyl and aryl amines. A mixed MeCN/EtOH solvent system was found
Radical Trifluoromethoxylation of Arenes Triggered by a Visible‐Light‐Mediated N−O Bond Redox Fragmentation
作者:Benson J. Jelier、Pascal F. Tripet、Ewa Pietrasiak、Ivan Franzoni、Gunnar Jeschke、Antonio Togni
DOI:10.1002/anie.201806296
日期:2018.10.15
method enables non‐directed functionalization of C−H bonds on a range of substrates, providing access to aryl trifluoromethyl ethers. This light‐driven process is distinctly different from conventional procedures and occurs through an OCF3 radical mechanism mediated by a photoredox catalyst, which triggers an N−O bond fragmentation. The pyridinium‐based trifluoromethoxylation reagent is bench‐stable and
Palladium(<scp>ii</scp>)-catalysed ortho-arylation of N-benzylpiperidines
作者:Peng Wen Tan、Maxwell Haughey、Darren J. Dixon
DOI:10.1039/c5cc00410a
日期:——
Pd(II)-catalysed ortho-arylation of benzylic heterocycles with arylboronic acid pinacol esters (Ar-BPin) via directed C-H bond activation to generate the desired biaryl products is reported. This methodology is efficient and applicable to a wide range of functionalised Ar-BPin and benzylic heterocycles, allowing the direct synthesis of important biaryl motifs in modest to good yield.
Transformations of Aryl Ketones via Ligand‐Promoted C−C Bond Activation
作者:Hanyuan Li、Biao Ma、Qi‐Sheng Liu、Mei‐Ling Wang、Zhen‐Yu Wang、Hui Xu、Ling‐Jun Li、Xing Wang、Hui‐Xiong Dai
DOI:10.1002/anie.202006740
日期:2020.8.17
The coupling of aromatic electrophiles (aryl halides, aryl ethers, aryl acids, aryl nitriles etc.) with nucleophiles is a core methodology for the synthesis of aryl compounds. Transformations of arylketones in an analogous manner via carbon–carbon bond activation could greatly expand the toolbox for the synthesis of aryl compounds due to the abundance of arylketones. An exploratory study of this