Li Xuejing, Deng Xingwang, Coyne Anthony G, Srinivasan Rajavel
School of Pharmaceutical Science and Technology (SPST), Tianjin University, 92 Weijin Road, Building 24, Nankai District, Tianjin, 300072, P.R. China.
University Chemical Laboratory, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK.
Chemistry. 2019 Jun 18;25(34):8018-8023. doi: 10.1002/chem.201901633. Epub 2019 May 20.
Herein, we report the meta-nitration of arenes bearing ortho/para directing group(s) using the iridium-catalyzed C-H borylation reaction followed by a newly developed copper(II)-catalyzed transformation of the crude aryl pinacol boronate esters into the corresponding nitroarenes in a one-pot fashion. This protocol allows the synthesis of meta-nitrated arenes that are tedious to prepare or require multistep synthesis using the existing methods. The reaction tolerates a wide array of ortho/para-directing groups, such as -F, -Cl, -Br, -CH , -Et, -iPr -OCH , and -OCF . It also provides regioselective access to the nitro derivatives of π-electron-deficient heterocycles, such as pyridine and quinoline derivatives. The application of this method is demonstrated in the late-stage modification of complex molecules and also in the gram-scale preparation of an intermediate en route to the FDA-approved drug Nilotinib. Finally, we have shown that the nitro product obtained by this strategy can also be directly converted to the aniline or hindered amine through Baran's amination protocol.
在此,我们报道了带有邻位/对位导向基团的芳烃的间位硝化反应,该反应采用铱催化的C-H硼化反应,随后是新开发的铜(II)催化的一锅法将粗制芳基频哪醇硼酸酯转化为相应的硝基芳烃。该方法能够合成间位硝化的芳烃,而这些芳烃使用现有方法制备繁琐或需要多步合成。该反应耐受多种邻位/对位导向基团,如-F、-Cl、-Br、-CH₃、-Et、-iPr、-OCH₃和-OCF₃。它还能区域选择性地获得缺π电子杂环的硝基衍生物,如吡啶和喹啉衍生物。该方法的应用在复杂分子的后期修饰以及美国食品药品监督管理局(FDA)批准的药物尼洛替尼合成路线中一种中间体的克级制备中得到了证明。最后,我们表明通过该策略获得的硝基产物也可以通过巴兰胺化方案直接转化为苯胺或受阻胺。