Functionalization of Azacalixaromatics by Cu(II)-Catalyzed Oxidative Cross-Coupling Reaction between the Arene C–H Bond and Boronic Acids
作者:Yang Liu、Chao Long、Liang Zhao、Mei-Xiang Wang
DOI:10.1021/acs.orglett.6b02530
日期:2016.10.7
Catalyzed by Cu(ClO4)2·6H2O under mild aerobic conditions using air as the oxidant, azacalix[1]arene[3]pyridines underwent a highly efficient oxidative cross-coupling reaction with a large number of aryl-, alkenyl-, and alkylboronic acids to afford diverse functionalized macrocycles. Stoichiometric reactions of an arylboronic acid with isolated and structurally well-defined high valent organocopper
Synthesis of Functionalized Azacalix[1]arene[3]pyridine Macrocycles from Cu(II)-Mediated Direct Amination Reactions of Arene through High Valent Arylcopper(III) Intermediates
作者:Yang Liu、Qian Zhang、Qing-Hui Guo、Mei-Xiang Wang
DOI:10.1021/acs.joc.6b01448
日期:2016.11.4
presence of K3PO4 under mild conditions, azacalix[1]arene[3]pyridines underwent arene C–H bond amination with a number of sulfonamides, imides, and saccharin to afford the diverse C–N bond forming products. Based on different reactivity between arylcopper(II) and arylcopper(III) compounds toward nitrogen nucleophiles, the reaction proceeded most likely through arene C–H bond metalation via reactive arylcopper(III)
在温和条件下,在K 3 PO 4存在下,由Cu(ClO 4)2介导,对azacalix [1] arene [3]吡啶进行芳烃C-H键胺化反应,并用许多磺酰胺,酰亚胺和糖精进行处理,以提供多种C–N键形成产品。基于芳基铜(II)和芳基铜(III)化合物对氮亲核试剂的不同反应性,该反应最有可能通过芳烃铜键通过反应性芳基铜(III)中间体进行金属化以及它们与源自氮的去质子化的氮阴离子的结合而进行。 p K a的氮亲核试剂的酸性NH键(DMSO)<17.5,然后进行还原消除。该研究不仅提供了方便,直接的途径,以其他方式不易获得的官能化杂芳基芳烃,也丰富了我们对高价有机铜化学的理解。
Cu(OTf)<sub>2</sub>-Catalyzed Selective Arene C–H Bond Hydroxylation and Nitration with KNO<sub>2</sub> as an Ambident <i>O</i>- and <i>N</i>-Nucleophile via a Cu(II)–Cu(III)–Cu(I) Mechanism
作者:Hu Zhang、Liang Zhao、De-Xian Wang、Mei-Xiang Wang
DOI:10.1021/ol401453f
日期:2013.8.2
Cu(OTf)2-catalyzed selective arene C–H bond hydroxylation and nitration reactions of azacalix[1]arene[3]pyridines were achieved using KNO2 as an ambident O- and N-nucleophile under very mild aerobic conditions to yield functionalized azacalixaromatics. The reaction, which selectivity between hydroxylation and nitration was modulated by the reaction medium employed, proceeded through a Cu(II)–Cu(III)–Cu(I) mechanism
Direct Synthesis of High-Valent Aryl–Cu(II) and Aryl–Cu(III) Compounds: Mechanistic Insight into Arene C–H Bond Metalation
作者:Hu Zhang、Bo Yao、Liang Zhao、De-Xian Wang、Bo-Qing Xu、Mei-Xiang Wang
DOI:10.1021/ja412615h
日期:2014.4.30
Copper and its salts are abundant, inexpensive, and eco-friendly and have been used as the surrogates of noble metals to effect arene C-H bond activation and transformations. Despite of the recent significant progress of the study, syntheses of high-valent arylcopper(II-III) compounds are still very rare and mechanisms of copper(II)-catalyzed reactions remain elusive. With the use of azacalix[1]arene[3]pyridines
铜及其盐储量丰富、价格低廉且对环境友好,已被用作贵金属的替代物来影响芳烃 CH 键的活化和转化。尽管最近该研究取得了重大进展,但高价芳基铜 (II-III) 化合物的合成仍然非常罕见,铜 (II) 催化反应的机制仍然难以捉摸。使用氮杂杯[1]芳烃[3]吡啶作为平台,在环境条件下由Cu(ClO4)2反应有效地合成了许多芳基铜(II)化合物。得到的芳基-Cu(II) 化合物含有前所未有的(取代的)苯基-Cu(II) σ-键,在大气条件下稳定,并且可以通过游离铜 (II) 离子或氧酮进行容易的氧化反应,得到芳基铜(III) 收率良好的化合物。芳基铜 (II) 和芳基铜 (III) 化合物均通过 XRD、XPS 和 NMR 方法明确表征。包括反应动力学、LFER 和 KIE 在内的实验证据以及理论计算表明,Cu(ClO4)2 介导的芳烃 CH 键活化似乎是通过亲电芳香族金属化途径进行的。这里报道的