Synthesis of 2-Aryl-2H-benzotrizoles from Azobenzenes and N-Sulfonyl Azides through Sequential Rhodium-Catalyzed Amidation and Oxidation in One Pot
摘要:
An efficient synthetic method of 2-aryl-2H-benzotriazoles from nonprefunctionalized azobenzenes and N-sulfonyl azides via sequential Rh-catalyzed amidation (C-N bond formation) and oxidation (N-N bond formation) with PhI(OAc)(2) in one pot is reported.
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]
Site-Selective C-H Amidation of Azobenzenes with Dioxazolones under Rhodium Catalysis
作者:Neeraj Kumar Mishra、Yongguk Oh、Mijin Jeon、Sangil Han、Satyasheel Sharma、Sang Hoon Han、Sung Hee Um、In Su Kim
DOI:10.1002/ejoc.201601096
日期:2016.10
The rhodium(III)-catalyzed amidation reaction of azobenzenes with dioxazolones is described. This strategy allows the facile and efficient construction of highly substituted ortho-amidated azobenzenes via direct C-H cleavage approach. A range of substrate scope, excellent levels of chemoselectivity as well as high functional group tolerance were observed. In addition, this protocol was used to generate
Selective Rhodium-Catalyzed C–H Amidation of Azobenzenes with Dioxazolones under Mild Conditions
作者:Bomi Jeon、Uiseong Yeon、Jeong-Yu Son、Phil Ho Lee
DOI:10.1021/acs.orglett.6b02250
日期:2016.9.16
A synthetic method for a wide range of amidated azobenzenes is developed from the selective rhodium-catalyzed C–H amidation reaction of symmetrical as well as unsymmetrical azobenzenes with alkyl-, aryl-, and heteroaryl-substituted dioxazolones undermildconditions. Diamidation of azobenzenes and amidation of monoamidated azobenzenes were also demonstrated.
Synthesis of (2
<i>H</i>
)‐Indazoles from Azobenzenes Using Paraformaldehyde as a One‐Carbon Synthon
作者:Rina Chun、Saegun Kim、Sang Hoon Han、Sangil Han、Suk Hun Lee、Neeraj Kumar Mishra、Young Hoon Jung、Hyung Sik Kim、In Su Kim
DOI:10.1002/adsc.201801547
日期:2019.4
hydroxymethylation followed by intramolecular annulation of azobenzenesusingparaformaldehyde as a valuable C1‐feedstock is described. The method is readily extended to the coupling reaction between azobenzenes and trifluoroacetaldehyde. This transformation efficiently produces a range of C3‐unsubstituted and C3‐trifluoromethylated (2H)‐indazoles, which are important targets in the development of novel
<i>tert-</i>Butyl Nitrite Mediated Regiospecific Nitration of (<i>E</i>)-Azoarenes through Palladium-Catalyzed Directed CH Activation
作者:Biju Majhi、Debasish Kundu、Sabir Ahammed、Brindaban C. Ranu
DOI:10.1002/chem.201403325
日期:2014.8.4
An efficient protocol for the Pd‐catalyzed regiospecific ortho‐nitration of (E)‐azoarenes has been achieved for the first time using tBuONO as a nitrating agent under atmospheric oxygen. A series of both symmetrical and unsymmetrical azoarenes were nitrated efficiently by this procedure providing excellent chemo‐ and regioselectivity and compatibility with a broad array of functional groups.