18264-99-8

Upstream product

• 88-73-3 2-Chloronitrobenzene 
• 103-84-4 Acetanilid 
• 1227476-15-4 Azobenzene 
• 98-95-3 nitrobenzene 
• 586-96-9 Nitrosobenzene 
• 95-51-2 o-chloroaniline 

Downstream Products

• 949-37-1 1-(2-chlorophenyl)-2-phenylhydrazine 
• 185392-56-7 RhCl₂(P(C₆H₅)3)2(C₆H₄NNC₆H₅) 

Relevant academic research and scientific papers

Anion ligand promoted selective C-F bond reductive elimination enables C(sp2)-H fluorination

A detailed mechanism study on the anion ligand promoted selective C-H bond fluorination is reported. The role of the anion ligand has been clarified by experimental evidence and DFT calculations. Moreover, the nitrate promoted C-F bond reductive elimination enabled a selective C-H bond fluorination of various symmetric and asymmetric azobenzenes to access diverse o-fluoroanilines.

Hypercrosslinked Polymer Platform-Anchored Single-Site Heterogeneous Pd-NHC Catalysts for Diverse C-H Functionalization

We demonstrate a new class of hypercrosslinked polymer (HCP) platform-Anchored single-site heterogenized Pd-NHC catalysts for multipurpose C-H functionalization reactions. This new class is represented by a set of three catalysts, viz., HCP-B-MeNHC-Pd, HCP-B-BnNHC-Pd, and HCP-TPM-MeNHC-Pd, having a variation on the structural feature of the anchoring polymeric platform. All three catalysts were fully characterized via diverse solid-state characterization and analytical techniques such as X-ray photoelectron spectroscopy, 13C cross-polarization magic-Angle-spinning nuclear magnetic resonance, field-emission scanning electron microscopy, energy-dispersive X-ray analysis, thermogravimetric analysis, and inductively coupled plasma-optical emission spectrometry. Three types of regularly practiced and very useful C-H functionalization reactions, viz., C-H halogenation, acetoxylation, and arylation, are tested with the new catalysts and found to be highly compatible and successful. With the HCP-TPM-MeNHC-Pd catalyst, up to 85, 75, and 70% yields of the functionalized products were achieved for the halogenation, acetoxylation, and arylation reactions, respectively. Demanding attributes such as enhanced activity, heterogeneity, and recyclability are offered by this new system, making it a promising candidate in the field of heterogeneous C-H functionalization, where only a few efficient catalysts are available.

Hydrogen peroxide based oxidation of hydrazines using HBr catalyst

Azo compounds (RN = NR′) are an important class of organic molecules that find wide application in organic synthesis. Herein, we report an efficient, practical and metal-free oxidation of hydrazines (RNH-NHR’) to azo compounds using 5 mol% HBr and hydrogen peroxide as terminal oxidant. This new method has been demonstrated by 40 examples with excellent yields. In addition, we showcased two examples of the one-pot sequential reactions involving our hydrazine oxidation/hydrolysis/Heck reaction or Cu-catalyzed N-arylation with aryl boronic acid. The distinct advantages of this protocol include metal-free catalysis, waste prevention, and easy operation.

Convenient Electrocatalytic Synthesis of Azobenzenes from Nitroaromatic Derivatives Using SmI2

The synthesis of azobenzenes has been a long-standing challenge. Their current preparation at a preparative or industrial scale requires stoichiometric amounts of environmentally unfriendly reactants. Herein, we demonstrate that the catalytic use of electrogenerated samarium diiodide (SmI2) could promote, in one-step synthesis, the reduction of nitrobenzenes into azobenzenes in high yields under mild reaction conditions. This catalytic procedure contains many elements satisfying a sustainable chemical process for the preparation of one of the most widely wanted family of chemical compounds. The easy synthetic procedure, and the absence of precious metals, bases, and nonhazardous substances, already makes our catalytic procedure a serious alternative to currently available methods. This is a promising method for the efficient synthesis of both symmetrical and asymmetrical azo compounds with a high functional group tolerance.

Aromatic amine oxidation process for preparing aromatic azobenzene method

The invention relates to a method for preparing an aromatic azo compound by utilizing aromatic amine oxidation. In the method, air or oxygen serves as an oxygen source, and under the effect of a catalyst, aromatic amine is oxidized into the aromatic azo compound. The method is high in oxidization efficiency and product yield; the air or the oxygen serves as the oxygen source, and the method is economical and environmentally friendly. The product and the catalyst can be separated easily, and the aftertreatment is simple. The catalyst is easy to reuse, and the method has very good application prospect.

Deoxygenative coupling of nitroarenes for the synthesis of aromatic azo compounds with CO using supported gold catalysts

A facile and efficient catalytic system based on a mesostructured ceria-supported gold (Au/meso-CeO2) catalyst was developed for the synthesis of various aromatic azo compounds by the reductive coupling of the corresponding nitroaromatics, using CO as the sole deoxygenative reagent, under additive-free and mild reaction conditions.

Gold-catalyzed direct hydrogenative coupling of nitroarenes to synthesize aromatic azo compounds

The azo linkage is a prominent chemical motif which has found numerous applications in materials science, pharmaceuticals, and agrochemicals. Described herein is a sustainable heterogeneous-gold-catalyzed synthesis of azo arenes. Available nitroarenes are deoxygenated and linked selectively by the formation of N-N bonds using molecular H2 without any external additives. As a result of a unique and remarkable synergy between the metal and support, a facile surface-mediated condensation of nitroso and hydroxylamine intermediates is enabled, and the desired transformation proceeds in a highly selective manner under mild reaction conditions. The protocol tolerates a large variety of functional groups and offers a general and versatile method for the environmentally friendly synthesis of symmetric or asymmetric aromatic azo compounds.

A novel synthesis of unsymmetrical azo aromatics inaccessible by diazo-coupling reaction

A novel synthesis of unsymmetrical azo aromatics inaccessible by diazo-coupling reaction is reported. The synthesis involved the reaction of acetanilides with nitroarenes under moderate reaction conditions. A reaction pathway via a nitrosoarene intermediate involving elimination of the elements of the acetate anion, is proposed.

Kinetics of the Chlorination of Azobenzene and Comparison with Azoxybenzene

The activating effect of the phenylazo substituent in electrophilic substitution has been examined.The rates and partial rate factors for chlorination of azobenzene with molecular chlorine and protonated chlorine acetate have been determined relative to benzene.Whereas the chlorine acetate reaction proceeds readily (relative rate 4900) there is virtually no activation to chlorination by molecular chlorine.Complexes between azobenzene and bromine were, however, isolated and characterized.Their formation implies that during molecular halogenation reactions the electrop hile is essentially unavailable.The relative chlorination rates for azobenzene and azoxybenzene have also been established: the phenylazo group is more activating towards protonated chlorine acetate whereas azoxybenzene (which does not complex with halogens) is the more reactive with molecular chlorine.The chlorination results confirm the versatility of the phenylazo group which is the first substituent for which kinetic data have been obtained quantifying activation of aromatic electrophilic, radical and nucleophilic substitution.