Synthesis of biaryls via the Suzuki-Miyauracoupling (SMC) reaction using nitroarenes as an electrophilic coupling partners is described. Mechanistic studies have revealed that the catalytic cycle of this reaction is initiated by the cleavage of the aryl-nitro (Ar-NO2) bond by palladium, which represents an unprecedented elemental reaction.
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。
Suzuki reaction of aryl bromides and arylboronicacids is developed. The cross-coupling reactions can be performed at room temperature using 5.0 equiv. of Et3N as solvent and base without any ligands, and affording biaryl products in good yields. In addition, the chemoselecitive Suzuki reaction of bromo-N-methyliminodiacetic acid (MIDA) boronates with arylboronicacids can be achieved in this system, and