Synthesis of Amido-N-imidazolium Salts and their Applications as Ligands in Suzuki-Miyaura Reactions: Coupling of Hetero- aromatic Halides and the Synthesis of Milrinone and Irbesartan
作者:Manian Rajesh Kumar、Kyungho Park、Sunwoo Lee
DOI:10.1002/adsc.201000592
日期:2010.12.17
catalytic system based on palladium-amido-N-heterocyclic carbenes for Suzuki–Miyaura coupling reactions of heteroaryl bromides is described. A variety of sterically bulky, amido-N-imidazolium salts were synthesized in high yields from the corresponding anilines. This catalytic system effectively promoted Suzuki–Miyaura couplings of heteroaryl bromides and chlorides with a range of boronic acids to
描述了基于钯-酰胺基-N-杂环卡宾的Suzuki-Miyaura杂芳基溴化物偶联反应的新催化体系。从相应的苯胺以高收率合成了各种空间庞大的酰胺基-N-咪唑鎓盐。该催化体系有效地促进了杂芳基溴化物和氯化物与一系列硼酸的Suzuki-Miyaura偶联,从而以高收率得到了相应的芳基化合物。随着取代基空间位阻的增加,产率增加。特别是,1-(2,6-二异丙基)-3- ñ - (2,4,6-三-叔-butylphenylacetamido)咪唑鎓溴化物(4BC)在2-溴吡啶和苯基硼酸的偶联反应中显示出850,000 TON。此外,药物化合物如米力农和厄贝沙坦是通过Suzuki-Miyaura偶联,使用体积庞大的酰胺基-N-咪唑鎓盐(4bc)作为配体合成的。