Palladium-catalyzed denitrative Suzuki coupling of nitroarenes using 2-aryl-5-(2,4,6-triisopropylphenyl)-2,3-imidazolylidene[1,5-a]pyridines as the ligands is described. The key to success is the use of the NHC ligands which show strong donating ability and suitable steric hindrance allowing the successful oxidative addition of Ar–NO2 bonds. Both aromatic and aliphatic boronic acids are tolerated,
描述了使用2-芳基-5-(2,4,6-三异丙基苯基)-2,3-咪唑基亚甲基[1,5- a ]吡啶作为配体的钯催化硝基芳烃的反硝化Suzuki偶联。成功的关键是使用NHC配体,该配体显示出强大的供体能力和适当的空间位阻,可以成功地氧化添加Ar–NO 2键。芳族和脂族硼酸都可以被接受,并且以良好或优异的收率获得了各种联苯和烷基芳烃。
Hydrophilic CNC-Pincer Palladium Complexes: A Source for Highly Efficient, Recyclable Homogeneous Catalysts in Suzuki–Miyaura Cross-Coupling
and aryl bromides is performed in neat water with excellent to quantitative yields by means of a new CNC-pincerpalladiumcatalyst that is soluble in water due to its para-carboxy group. Extremely high turnover numbers and frequencies combined with a remarkable robustness allow an effective catalyst reuse in sustainable conditions.
Nickel-Catalyzed Csp<sup>2</sup>–Csp<sup>3</sup>Bond Formation via C–F Bond Activation
作者:Yee Ann Ho、Matthias Leiendecker、Xiangqian Liu、Chengming Wang、Nurtalya Alandini、Magnus Rueping
DOI:10.1021/acs.orglett.8b02351
日期:2018.9.21
A nickel-catalyzed cross coupling of aryl fluorides via C–Fbondactivation has been developed. The alkylation method allows selective replacement of aryl fluorides by alkyl groups and enables the synthesis of diverse and otherwise difficult to access scaffolds in good yields.
A Ni‐catalyzed C−F bond functionalization of unactivated arylfluorides with oxazoles as coupling partners was developed. Various arylated oxazoles could be obtained in moderate to good yields in the presence of Ni(cod)2/IMes catalytic system. A rapid synthesis of natural product texaline was also demonstrated using this protocol. This transformation could be potentially utilized in regioselective
Base- and metal-free C–H direct arylations of naphthalene and other unbiased arenes with diaryliodonium salts
作者:Susana Castro、Juan J. Fernández、Rubén Vicente、Francisco J. Fañanás、Félix Rodríguez
DOI:10.1039/c2cc34592g
日期:——
A novel metal-free direct arylation of unbiased arenes with diaryliodonium triflates in a process where the use of solvents and additives is not required has been established.