A mild CuBr–NMO oxidative system for the coupling of anilines leading to aromatic azo compounds
作者:Shikha Singh、Parul Chauhan、Makthala Ravi、Isha Taneja、Wahajuddin Wahajuddin、Prem. P. Yadav
DOI:10.1039/c5ra12535a
日期:——
been developed utilizing CuBr with N-methylmorpholine N-oxide (NMO/NMMO) for the oxidative coupling of anilines to access symmetrical and unsymmetrical azocompounds in high yield. The reactivity was found to be governed by electronic and stericfactors of anilines.
Rhodium(III)-Catalyzed Synthesis of Cinnolinium Salts from Azobenzenes and Alkynes: Application to the Synthesis of Indoles and Cinnolines
作者:Krishnamoorthy Muralirajan、Chien-Hong Cheng
DOI:10.1002/chem.201300922
日期:2013.5.10
Versatile salts: A new rhodium‐catalyzed synthesis of cinnolinium salts from various azobenzenes and alkynes under air is described. These salts readily transform into three important classes of products, including indoles, indoloindoles, and cinnolines (see scheme).
α-Selective Allylation of Azo Compounds Using Allylic Barium Reagents
作者:Akira Yanagisawa、Takuya Jitsukawa、Kazuhiro Yoshida
DOI:10.1055/s-0032-1318306
日期:——
The addition of allylic barium reagents to azo compounds was achieved with high α-regioselectivity. The double-bond geometry of allylic barium reagents was retained throughout the reaction at –78 °C and E- or Z-enriched allylic hydrazines were selectively obtained from the corresponding allylic barium reagents. An allylic hydrazine was efficiently converted into an allylic amine by reductive N–N bond
以高α-区域选择性将烯丙基钡试剂添加到偶氮化合物中。烯丙基钡试剂的双键几何结构在 –78 °C 的整个反应过程中保持不变,并且从相应的烯丙基钡试剂中选择性地获得富含 E 或 Z 的烯丙基肼。通过还原性 N-N 键断裂,烯丙基肼被有效地转化为烯丙基胺。
Bifunctional Cs−Au/Co
<sub>3</sub>
O
<sub>4</sub>
(Basic and Redox)‐Catalyzed Oxidative Synthesis of Aromatic Azo Compounds from Anilines
作者:Charles O. Oseghale、Dele Peter Fapojuwo、Oyekunle Azeez Alimi、Christianah Aarinola Akinnawo、Batsile M. Mogudi、Oluwatayo Racheal Onisuru、Reinout Meijboom
DOI:10.1002/ejoc.202100976
日期:2021.9.24
An alkali-promoted gold-based (Cs−Au/Co3O4) catalyst with redox and basic properties was designed to perform the oxidative coupling of anilines to symmetrical and unsymmetrical aromatic azo compounds. The process proceeded under milder reaction conditions without base additive and molecular O2 oxidant (using air). The catalyst performance was easily correlated to the effect of lattice oxygen, low reduction
设计了一种具有氧化还原和碱性性质的碱促进金基(Cs-Au/Co 3 O 4)催化剂,用于将苯胺氧化偶联到对称和不对称的芳香偶氮化合物上。该过程在温和的反应条件下进行,没有碱添加剂和分子 O 2氧化剂(使用空气)。催化剂性能很容易与晶格氧、低还原温度和增加的碱性位点浓度的影响相关联,可重复使用性达到六个循环。
Cobalt-Catalyzed Oxidative Annulation of Nitrogen-Containing Arenes with Alkynes: An Atom-Economical Route to Heterocyclic Quaternary Ammonium Salts
nitrogen‐containing arenes with alkynes proceeds by C−Hactivation, thus leading to biologically useful quaternary ammonium salts, including pyridoisoquinolinium, cinnolinium, isoquinolinium, and quinolizinium salts, in high yields. The results are comparable to those reactions catalyzed by rhodium and ruthenium complexes. The transformation of the salts into variousN‐heterocycles has also been demonstrated.