Polyfluoro-substituted unsymmetrical biaryl ethers were synthesized via a novel Ni-catalyzed cross-coupling reaction of polyfluoroarenes with arylboronic acids and oxygen. The polyfluorinated arenes presumably captured the phenoxide intermediate efficiently, which made the oxygen-insertion proceed smoothly via the SNAr protocol. The 18O labeling experiment demonstrated that the oxygen introduced into unsymmetrical diaryl ether originated from very trace amounts of oxygen in the reaction system. A plausible mechanism was also suggested.
通过一种新型
镍催化的交叉偶联反应,合成了多
氟取代的不对称双芳基醚,该反应涉及多
氟芳烃与芳基
硼酸和氧的反应。多
氟芳烃可能有效地捕获了苯氧中间体,使得通过亲核芳香取代(SNAr)途径顺利进行氧插入。通过同位素标记实验表明,引入不对称双芳基醚的氧来自反应体系中微量的氧。同时,还提出了一种可能的机理。