32388-07-1Relevant articles and documents
Green Hydrothermal Synthesis of Fluorescent 2,3-Diarylquinoxalines and Large-Scale Computational Comparison to Existing Alternatives
Amaya-García, Fabián,Caldera, Michael,Koren, Anna,Kubicek, Stefan,Menche, J?rg,Unterlass, Miriam M.
, p. 1853 - 1863 (2021/04/02)
Here, the hydrothermal synthesis (HTS) of 2,3-diarylquinoxalines from 1,2-diketones and o-phenylendiamines (o-PDAs) was achieved. The synthesis is simple, fast, and generates high yields, without requiring any organic solvents, strong acids or toxic catalysts. Reaction times down to 90 % in all cases). Moreover, it was shown that HTS has high compatibility: (i) hydrochlorides, a standard commercial form of amines, could be used directly as combined amine source and acidic catalyst, and (ii) Boc-diprotected o-PDA could be directly employed as substrate that underwent HT deprotection. A systematic large-scale computational comparison of all reported syntheses of the presented quinoxalines from the same starting compounds showed that this method is more environmentally friendly and less toxic than all existing methods and revealed generic synthetic routes for improving reaction yields. Finally, the application of the synthesized compounds as fluorescent dyes for cell staining was explored.
The Direct Synthesis of Imines, Benzimidazoles and Quinoxalines from Nitroarenes and Carbonyl Compounds by Selective Nitroarene Hydrogenation Employing a Reusable Iron Catalyst
B?umler, Christoph,Kempe, Rhett
supporting information, p. 8989 - 8993 (2018/05/30)
The “replacement” of noble metals by earth abundant metals is a desirable aim in catalysis and a possible way of conserving rare elements. The “replacement” is especially attractive if novel selectivity patterns are observed permitting the development of novel coupling reactions. Herein, we report on a novel, robust and reusable iron catalyst, which permits the selective hydrogenation of nitroarenes in the presence of hydrogenation-sensitive functional groups. Based on the selectivity pattern observed, the direct iron-catalyzed synthesis of imines and benzimidazoles from nitroarenes and aldehydes becomes feasible. In addition, we introduce the direct synthesis of quinoxalines from nitroarenes and diketones applying our catalyst.
One-pot synthesis of quinoxalines from reductive coupling of 2-nitroanilines and 1,2-diketones using indium
Go, Ahra,Lee, Geunsoo,Kim, Jaeho,Bae, Seolhee,Lee, Byung Min,Kim, Byeong Hyo
, p. 1215 - 1226 (2015/03/04)
The one-pot reduction-cyclization of 2-nitroanilines and 1,2-diketones to give quinoxalines was investigated. Using indium and an appropriate acid such as acetic acid or indium(III) chloride, various quinoxaline derivatives including 2,3-dialkylquinoxalines, 2,3-diphenylquinoxalines, 2,3-di-2-thiophenylquinoxalines, 2,3-di(pyridin-2-yl)quinoxalines, and dibenzo[a,c]phenazines were synthesized in moderate to excellent yield.
