Palladium-catalyzed phosphination and amination through C H bond functionalization on biphenyl: Amido-substituent as directing group
作者:I-Hsiang Kao、Ching-Yu Wang、Yu-Chang Chang、Chu-Lun Wu、Yu-Jen Chiu、Fung-E Hong
DOI:10.1016/j.tet.2018.12.007
日期:2019.1
found to greatly affect the ratio distribution of products 3 and 4. By contrast, substituents on various locations of the biphenyl in 1 do not influence much on the outcome of the products distribution. A reaction mechanism is proposed to account for these experimental observations. Computational studies employing Density Functional Theory methods (DFT) on this proposed mechanism found that the electron
的形成Ñ(2' - - (二苯基磷酰基) - [1,1'-联苯] -2-基)-2,3,4,5,6- pentafluorobenzamide(3_eaaa)已经通过取得的钯-催化的和Ag(I)辅助N -([[1,1'-联苯] -2-基)-2,3,4,5,6-五氟苯甲酰胺(1_eaa)的C H官能团通过磷化作用和二苯基膦氧化物的存在(2_a)。该反应伴随有少量咔唑衍生物(9 H-咔唑-9-基)(全氟苯基)甲酮(4_eaa)。3_eaaa和4_eaa的晶体结构均通过X射线晶体衍射法测定。实际上,磷酸化发生在1_eaa环间环的邻位。发现在1的酰胺片段上具有各种吸电子/给电子能力的取代基极大地影响了产物3和4的比例分布。相反,在1中联苯的各个位置上的取代基对产品分配的结果影响不大。提出了一种反应机理来解释这些实验观察。对这种提出的机制采用密度泛函理论方法(DFT)进行的计算研究发现,中间体II中钯