Herein we report an effective and simple preparation method of substituted azoxybenzenes by reductive dimerization of nitrosobenzenes. This procedure requires no additional catalyst/reagent and can be applied to substrates with a wide range of substitution patterns.
Gold Catalysts Can Generate Nitrone Intermediates from a Nitrosoarene/Alkene Mixture, Enabling Two Distinct Catalytic Reactions: A Nitroso-Activated Cycloheptatriene/Benzylidene Rearrangement
作者:Sayaji Arjun More、Rahul Dadabhau Kardile、Tung-Chun Kuo、Mu-Jeng Cheng、Rai-Shung Liu
DOI:10.1021/acs.orglett.1c01857
日期:2021.7.16
Gold-catalyzedreactions of cycloheptatrienes with nitrosoarenes yield nitrone derivatives efficiently. This reaction sequence enables us to develop gold-catalyzed aerobic oxidations of cycloheptatrienes to afford benzaldehyde derivatives using CuCl and nitrosoarenes as co-catalysts (10–30 mol %). Our density functional theory calculations support a novel nitroso-activated rearrangement, tropylium
Synthesis and Isomerization Studies of Cyclotrisazobiphenyl
作者:Raphael Reuter、Hermann A. Wegner
DOI:10.1002/chem.201002671
日期:2011.3.1
We report an efficient synthesis of cyclotris[(E)‐3′‐(biphenyl‐3‐yldiazenyl)] compounds (CTBs). An unsubstituted CTB molecule is accessible in four steps in 10 % yield overall, whereas a hexa(methoxymethyl ether) CTB analogue was prepared in nine steps (26 % yield). The final macrocyclization step was accomplished in up to 80 % yield by using a metal‐template effect. Furthermore, the photochromic properties
Enantioselective Oxidative Coupling of β-Ketocarbonyls and Anilines by Joint Chiral Primary Amine and Selenium Catalysis
作者:Wanting Chen、Yanni Wang、Xueling Mi、Sanzhong Luo
DOI:10.1021/acs.orglett.9b02636
日期:2019.10.18
An enantioselective primary amine-catalyzed total N-selective nitroso aldol reaction (N-NA) was achieved through the oxidation of primary aromatic amines to the corresponding nitrosoarenes catalyzed by selenium reagents and 30% H2O2. This protocol provides a facile and highly efficient access to α-hydroxyamino carbonyls bearing chiral quaternary centers under exceedingly mild and green reaction conditions
通过硒试剂和30%H 2 O 2催化伯芳族胺氧化为相应的亚硝基芳烃,可实现对映选择性伯胺催化的总N选择性亚硝基醛醇缩合反应(N -NA)。该方案可在极其温和和绿色的反应条件下,通过高度化学和对映体控制,轻松而高效地接近带有手性季中心的α-羟氨基羰基。
Continuous Flow Synthesis of Azoxybenzenes by Reductive Dimerization of Nitrosobenzenes with Gel‐Bound Catalysts
作者:Carsten J. Schmiegel、Patrik Berg、Franziska Obst、Roland Schoch、Dietmar Appelhans、Dirk Kuckling
DOI:10.1002/ejoc.202100006
日期:2021.3.19
In search for a new synthetic pathway for azoxybenzenes with different substitution patterns, an approach using a microfluidic reactor with gel‐bound proline organocatalysts under continuous flow inside a microfluidic device is presented.