77093-88-0

Upstream product

• 1074-12-0 phenylglyoxal hydrate 
• 102-51-2 4-methoxy-1,2-phenylenediamine 
• 52922-65-3 ω-(Methylthio)-ω-(methylsulfinyl)acetophenone 
• 79531-98-9 dimethyl phenacyl sulfonium iodide 
• 70-11-1 α-bromoacetophenone 
• 100-41-4 ethylbenzene 
• 100-42-5 styrene 
• 536-74-3 phenylacetylene 
• 96-96-8 4-methoxy-2-nitroaniline 
• 93-56-1 phenylethane 1,2-diol 
• 16133-49-6 5-methoxy-2-nitroaniline 
• 582-24-1 1-phenyl-2-hydroxyethanone 
• 64-04-0 phenethylamine 
• 122-78-1 phenylacetaldehyde 

Downstream Products

• 77093-90-4 7-methoxy-2-phenylquinoxaline 4-oxide 

Relevant academic research and scientific papers

Nickel-Catalyzed Direct Synthesis of Quinoxalines from 2-Nitroanilines and Vicinal Diols: Identifying Nature of the Active Catalyst

The inexpensive and simple NiBr2/1,10-phenanthroline system-catalyzed synthesis of a series of quinoxalines from both 2-nitroanilines and 1,2-diamines is demonstrated. The reusability test for this system was performed up to the seventh cycle, which afforded good yields of the desired product without losing its reactivity significantly. Notably, during the catalytic reaction, the formation of the heterogeneous Ni-particle was observed, which was characterized by PXRD, XPS, and TEM techniques.

Iron-catalyzed one-pot synthesis of quinoxalines: Transfer hydrogenative condensation of 2-nitroanilines with vicinal diols

Here, we report iron-catalyzed one-pot synthesis of quinoxalines via transfer hydrogenative condensation of 2-nitroanilines with vicinal diols. The tricarbonyl (η4-cyclopentadienone) iron complex, which is well known as the Kn?lker complex, catalyzed the oxidation of alcohols and the reduction of nitroarenes, and the corresponding carbonyl and 1,2-diaminobenzene intermediates were generated in situ. Trimethylamine N-oxide was used to activate the iron complex. Various unsymmetrical and symmetrical vicinal diols were applied for transfer hydrogenation, resulting in quinoxaline derivatives in 49-98% yields. A plausible mechanism was proposed based on a series of control experiments. The major advantages of this protocol are that no external redox reagents or additional base is needed and that water is liberated as the sole byproduct. This journal is

Iridium-Catalyzed [4+2] Annulations of β-Keto Sulfoxonium Ylides and o-Phenylenediamines: Mild and Facile Synthesis of Quinoxaline Derivatives

A synthetic method for quinoxaline derivatives from the [4+2] annulation of β-keto sulfoxonium ylides and o-phenylenediamine by using (Cp*IrCl2)2 catalyst is described. This novel protocol features mild reaction conditions, moderate to excellent yields, wide substrate scope, and high functional-group compatibility. Moreover, this cyclization strategy was successfully applied in late-stage modification for structurally complex bioactive compounds.

Homogeneous Nickel-Catalyzed Sustainable Synthesis of Quinoline and Quinoxaline under Aerobic Conditions

Dehydrogenative coupling-based reactions have emerged as an efficient route toward the synthesis of a plethora of heterocyclic rings. Herein, we report an efficacious, nickel-catalyzed synthesis of two important heterocycles such as quinoline and quinoxaline. The catalyst is molecularly defined, is phosphine-free, and can operate at a mild reaction temperature of 80 °C. Both the heterocycles can be easily assembled via double dehydrogenative coupling, starting from 2-aminobenzyl alcohol/1-phenylethanol and diamine/diol, respectively, in a shorter span of reaction time. This environmentally benign synthetic protocol employing an inexpensive catalyst can rival many other transition-metal systems that have been developed for the fabrication of two putative heterocycles. Mechanistically, the dehydrogenation of secondary alcohol follows clean pseudo-first-order kinetics and exhibits a sizable kinetic isotope effect. Intriguingly, this catalyst provides an example of storing the trapped hydrogen in the ligand backbone, avoiding metal-hydride formation. Easy regeneration of the oxidized form of the catalyst under aerobic/O2 oxidation makes this protocol eco-friendly and easy to handle.

Cooperative iridium complex-catalyzed synthesis of quinoxalines, benzimidazoles and quinazolines in water

Herein, an efficient methodology for the synthesis of a diverse class of N-heterocyclic moieties, such as quinoxalines, benzimidazoles and quinazolines, was developed in water using bio-renewable alcohols. The quinoxalines were successfully synthesized from a wide range of diamines and nitroamines with diols in air. Interestingly, benzimidazoles and quinazolines were synthesized with excellent isolated yields without using any external base. Finally, the preparative scale synthesis of various N-heterocycles and pharmaceutically active quinoxalines established the practicability of this protocol. For this iridium system, a metal-ligand cooperative mechanism was proposed based on kinetic and DFT studies.

C-N Bond Formation Catalyzed by Ruthenium Nanoparticles Supported on N-Doped Carbon via Acceptorless Dehydrogenation to Secondary Amines, Imines, Benzimidazoles and Quinoxalines

Ruthenium nanoparticles (NPs) supported on N-doped carbon (Ru/N?C) were prepared by the pyrolysis of cis-Ru(phen)2Cl2 loaded onto carbon powder (VULCAN XC72R) at 800 °C. Ru/N?C NPs (0.2 mol% Ru) selectively catalyzed either acceptorless dehydrogenation coupling (ADC) or auto-transfer-hydrogen (ATH) reactions of amines with alcohols to imines and secondary amines. Such selectivity could be controlled by the choice of alkali metal ion associated with the base. Under similar catalytic conditions, the ADC cross-coupling of diamines with primary alcohols or diols afforded the corresponding benzimidazoles and quinoxalines in good to excellent yields. This catalytic system displayed good activity, recyclability, and wide applicability to a diverse range of substrates.

One-Pot Protocol for the Synthesis of Imidazoles and Quinoxalines using N-Bromosuccinimide

N-bromosuccinimide (NBS)-mediated one-pot, green, efficient and practical synthesis of substituted imidazoles and quinoxalines has been achieved by the reaction of styrenes with N-arylbenzamidines and o-phenylenediamines, respectively, in a water:1,4-dioxane mixture. The reaction involves formation of an α-bromo ketone as an intermediate in the presence of NBS and water, followed by condensation with the N-arylbenzamidine and o-phenylenediamine. Use of an inexpensive NBS as a bromine source as well as an oxidant, water as a solvent and readily available starting materials makes this protocol environmentally benign and economically viable. Substituted imidazoles and quinoxalines were obtained in good to excellent yields with wide functional group compatibility. (Figure presented.).

Synthesis of 2-arylquinoxalines: Triarylstibane-catalyzed oxidative cyclization of α-hydroxy ketones with 1,2-diamines under aerobic conditions

The reaction of α-hydroxy ketones with 1,2-diamines in the presence of triphenylstibane (10 mol%) as catalyst led to the formation of 2-arylquinoxalines in moderate to good yield under aerobic conditions. This reaction is the first example of oxidative cy

Efficient synthesis of quinoxalines from 2-nitroanilines and vicinal diols via a rutheniumcatalyzed hydrogen transfer strategy

Via a ruthenium-catalyzed hydrogen transfer strategy, we have demonstrated a one-pot method for efficient synthesis of quinoxalines from 2-nitroanilines and biomass-derived vicinal diols for the first time. In such a synthetic protocol, the diols and the nitro group serve as the hydrogen suppliers and acceptors, respectively. Hence, there is no need for the use of external reducing agents. Moreover, it has the advantages of operational simplicity, broad substrate scope and the use of renewable reactants, offering an important basis for accessing various quinoxaline derivatives.

An "all-water" strategy for regiocontrolled synthesis of 2-aryl quinoxalines

A new synthetic strategy of tandem N-aroylmethylation-nitro reduction-cyclocondensation has been developed for the first and generalized regioselective synthesis of 2-aryl quinoxalines adopting "all water chemistry." Water plays the critical role through