Methods for synthesizing trifluoroethyl, difluoroethyl, pentafluoropropyl, and difluorophenethyl anilines by palladium-catalyzed coupling of fluoroalkylamines with aryl bromides and aryl chlorides are provided herein. The reaction is conducted with a weaker base such as KOPh in the presence of a catalyst derived from AdBippyPhos and [Pd(allyl)Cl]2. The reactions occur with catalyst loadings less than about 0.50 mol% and tolerate the presence of various functional groups that react with the strong bases that are typically used in Pd-catalyzed C-N cross coupling reactions of aryl halides. The resting state of the catalyst is the phenoxide complex, (BippyPhosPd(Ar)OPh); due to the electron-withdrawing property of the fluoroalkyl substituent, the turn-over limiting step of the reaction is reductive elimination to form the C-N bond.
本文提供了一种通过
钯催化氟烷胺与芳基
溴化物和芳基
氯化物偶联合成三
氟乙基、二
氟乙基、五
氟丙基和二
氟苯基
苯胺的方法。该反应在较弱的碱(如KOPh)存在下,在由AdBippyPhos和[Pd(allyl)Cl]2衍生的催化剂的作用下进行。反应发生在催化剂载体约为0.50 mol%以下的情况下,并且能够容忍与通常用于Pd催化芳基卤化物C-N交叉偶联反应中使用的强碱发生反应的各种功能基团的存在。催化剂的休息状态是苯氧基配合物(BippyPhosPd(Ar)OPh);由于氟烷基取代基具有电子吸引性,反应的限速步骤是还原消除形成C-N键。