Levitskiy Oleg A, Grishin Yuri K, Sentyurin Vyacheslav V, Magdesieva Tatiana V
Lomonosov Moscow State University, Chemistry Dept., Leninskie Gory 1/3, Moscow, 119991, Russia.
Chemistry. 2017 Sep 12;23(51):12575-12584. doi: 10.1002/chem.201702270. Epub 2017 Sep 1.
Comparative investigation of copper-assisted oxidative and reductive amination showed that the latter was preferable for the synthesis of bulky diarylamines. DFT estimation of the mechanism of copper(I)-assisted reductive amination of boronic acids with aryl nitroso compounds was performed and possible active species were identified. DFT estimation of the steric penalty revealed that the barrier for the transmetalation step for the hindered nitroso compound was almost the same as that for the unsubstituted one, whereas a bulky group in the boronic acid increased the activation energy. A DFT study of the influence of the electronic properties of the substituents in both reactants on the activation energy revealed that the optimal combination for the synthesis of unsymmetrical diarylamines to provide better yields was an electron-rich aryl boronic acid and an electron-deficient nitroso compound. By using these helpful guidelines, a series of new bulky diarylamines were obtained and fully characterized.
铜辅助氧化胺化和还原胺化的对比研究表明，后者更适合用于合成庞大的二芳基胺。对铜（I）辅助硼酸与芳基亚硝基化合物的还原胺化反应机理进行了密度泛函理论（DFT）估算，并确定了可能的活性物种。DFT对空间位阻的估算表明，受阻亚硝基化合物的转金属化步骤的势垒与未取代的亚硝基化合物几乎相同，而硼酸中的庞大基团增加了活化能。对两种反应物中取代基的电子性质对活化能影响的DFT研究表明，合成不对称二芳基胺以提供更好产率的最佳组合是富电子的芳基硼酸和缺电子的亚硝基化合物。通过使用这些有用的指导方针，获得了一系列新的庞大二芳基胺并进行了全面表征。
