Electrosynthesis of Azobenzenes Directly from Nitrobenzenes
作者:Yanfeng Ma、Shanghui Wu、Shuxin Jiang、Fuhong Xiao、Guo‐Jun Deng
DOI:10.1002/cjoc.202100470
日期:2021.12
The electrochemical reduction strategy of nitrobenzenes is developed. The chemistry occurs under ambient conditions. The protocol uses inert electrodes and the solvent, DMSO, plays a dual role as a reducing agent. Its synthetic value has been demonstrated by the highly efficient synthesis of symmetric, unsymmetric and cyclic azo compounds.
A new approach has been established for Rh(iii)-catalyzed direct aza oxidative cyclization of non-prefunctionalized azobenzenes to provide 2-aryl-2H-benzotriazoles in good yields.
<i>ortho</i>-Heteroarylation of Azobenzenes by Rh-Catalyzed Cross-Dehydrogenative Coupling: An Approach to Conjugated Biaryls
作者:Hong Deng、Hongji Li、Lei Wang
DOI:10.1021/acs.orglett.6b01277
日期:2016.7.1
A direct cross-dehydrogenative coupling strategy for ortho-C–H activation and functionalization of azobenzenes with heteroarenes in the presence of a Rh catalyst was developed. Excellent regioselectivity was achieved by azo-coordinated Rh to realize oxidative C–H/C–H cross-coupling, providing a series of π-conjugated biaryls in good yields.
Mechanism of Ti-Catalyzed Oxidative Nitrene Transfer in [2 + 2 + 1] Pyrrole Synthesis from Alkynes and Azobenzene
作者:Zachary W. Davis-Gilbert、Xuelan Wen、Jason D. Goodpaster、Ian A. Tonks
DOI:10.1021/jacs.8b03546
日期:2018.6.13
+ 2 + 1] pyrrolesynthesisfromalkynes and aryl diazenes is reported. This reaction proceeds through a formally TiII/TiIV redox catalytic cycle as determined by natural bond orbital (NBO) and intrinsic bond orbital (IBO) analysis. Kinetic analysis of the reaction of internal alkynes with azobenzene reveals a complex equilibrium involving Ti═NPh monomer/dimer equilibrium and Ti═NPh + alkyne [2 + 2]
molybdenum oxide compound, [N(C4H9)4]2[Mo6O19] (1), catalyzed selective oxidation of anilines with hydrogen peroxide as green oxidant. The oxidation of anilines can be realized in a fully selectively fashion to afford various symmetric/asymmetric azobenzene and azoxybenzene compounds, respectively, by changing additive and solvent, avoiding the use of stoichiometric metal oxidants. Preliminary mechanistic
在医药和工业应用中起重要作用的芳族偶氮化合物在合成中仍然面临巨大挑战。在此,我们报道了一种氧化钼化合物[N(C 4 H 9)4 ] 2 [Mo 6 O 19 ](1),用过氧化氢作为绿色氧化剂催化苯胺的选择性氧化。苯胺的氧化可以完全选择性地实现,通过改变添加剂和溶剂避免使用化学计量的金属氧化剂,从而分别提供各种对称/不对称的偶氮苯和and氧基苯化合物。初步的机理研究表明,高活性的反应性和难以捉摸的钼亚胺配合物是中间的。