An efficient protocol for the synthesis of quinoxaline derivatives at room temperature using molecular iodine as the catalyst

The use of molecular iodine as the catalyst for a one-pot synthesis of quinoxaline derivatives at room temperature is reported.     

Yb modified NaY zeolite： A recyclable and efficient catalyst for quinoxaline synthesis

In this study, Yb immobilized NaY zeolite catalyst（Yb/NaY） was obtained by a hydrothermal method and characterized by XRD, BET, FT-IR, ICP-AES, and NH3-TPD. The catalyst displayed good catalytic activity when applied to the synthesis of quinoxalines via condensation of a-hydroxyketones with 1,2-diamines,and could be reused several times without any loss of catalytic activity.     

Three-component tandem reactions of (2-arylsulfanyl-3-aryl-2-oxiranyl)(aryl)methanones and o-phenylenediamine: formation of quinoxalines

A series of new quinoxalines has been obtained from a one pot, three-component reaction of (2-arylsulfanyl-3-aryl-2-oxiranyl)(aryl)methanones with o-phenylenediamine in the presence of a catalytic amount of acetic acid. This reaction presumably involves a tandem oxirane aminolysis-cyclisation-elimination-air oxidation-condensation sequence.     

A versatile one-step method for the synthesis of benzimidazoles from quinoxalinones and arylenediamines via a novel rearrangement

A highly efficient and versatile method for the synthesis of benzimidazoles has been developed on the basis of the novel ring contraction of 3-aroyl- and 3-alkanoylquinoxalin-2-ones with 1,2-arylenediamines.     

Synthesis of Some New Heterocycles of Pharmaceutical Interest: Pyridinyl and Isoxazolyl Quinoxaline Derivatives

3‐(p‐Acetyl‐anilinomethyl)quinoxalin‐2(1H)‐one ( 3 ) was prepared by the reaction of 3‐bromomethyl‐quinoxalin‐2(1H)‐one ( 1 ) with p‐aminoacetophenone ( 2 ) in pyridine. Reaction of p‐acetylcompound ( 3 ) with aromatic aldehydes yield the corresponding chalcones ( 4a‐c ). Condensation of latter chalcones with malononitrile afforded cyanopyridines ( 5a‐c ). Also, the reaction of chalcones ( 4a‐c ) with hydroxylamine hydrochloride furnished isoxazoles ( 6a‐c ). The reaction of bromo compound ( 1 ) with p‐aminobenzophenone yield ( 8 ) which was condenced with hydrazine hydrate to get the corresponding hydrazone derivatives ( 9 ). Some of the synthesized compounds have been screened for their antimicrobial activity against various strains of bacteria and fungi.     

Oxidation of alkynes using PdCl2/CuCl2 in PEG as a recyclable catalytic system: one-pot synthesis of quinoxalines

Alkynes were oxidized efficiently using the catalytic amount of PdCl₂ and CuCl₂ in PEG-400 in the presence of water, providing excellent yields of the corresponding 1,2-diketones. A variety of alkynes were well-suited substrates for the oxidation under the described conditions. Further, the optimized conditions were successfully utilized for the one-pot synthesis of 2,3-disubstituted quinoxaline derivatives.     

[Cu2I2(C8H6N2)]∞晶体的水相合成与表征

近年来,d10金属配位聚合物的合成、结构和性质的研究引起了人们广泛的兴趣[1-3],CuXL(X＝Cl、Br和I,L＝含氮配体)配合物由于其结构的多样性和独特的发光性质而成为活跃的研究领域[1-10].     

Palladium-catalyzed C–H alkenylation of quinoxaline N-oxide enabled by a mono-N-protected amino acid

The efficient alkenylation of quinoxaline N-oxide was achieved via Pd-catalyzed C–H activation, using the assistance of a mono-N-protected amino acid. Further deoxygenation of the 2-styrylquinoxaline-N-oxides yielded the corresponding styrylquinoxaline derivatives.     

Direct solid-phase synthesis of quinoxaline-containing peptides

The solid-phase synthesis of a series of model dipeptides containing various 3-(quinoxalin-6-yl)alanine analogues is described. The method involves formation of a quinoxaline heterocycle by condensation between an α-dicarbonyl compound and a β-(3,4-diaminophenyl)alanine residue, immobilized on a solid support.