the synthesis of quinazolinones, quinoxalinones, benzooxazinones, and benzothiazoles from the reactions of α-keto acids with 2-aminobenzamides, benzene-1,2-diamines, 2-aminophenols, and 2-aminobenzenethiols, respectively, is described. The reactions were conducted under catalyst-free conditions, using water as the sole solvent with no additive required, and successfully applied to the synthesis of sildenafil
A niobium-catalyzed coupling reaction of α-keto acids with <i>ortho</i>-phenylenediamines: synthesis of 3-arylquinoxalin-2(1<i>H</i>)-ones
作者:Camila Ebersol、Nicole Rocha、Filipe Penteado、Márcio S. Silva、Daniela Hartwig、Eder J. Lenardão、Raquel G. Jacob
DOI:10.1039/c9gc02662b
日期:——
valuable 3-arylquinoxalin-2(1H)-ones was developed, by the reaction of α-keto acids with ortho-phenylenediamines in the presence of ammonium niobium oxalate (ANO) as a catalyst. The reactions were conducted in only 10 min under ultrasonic irradiation as an alternative energy source, affording water as the only co-product. A total of twenty-three different 3-arylquinoxalin-2(1H)-ones were selectively obtained
在草酸铌铵(ANO)存在下,通过α-酮酸与邻苯二胺的反应,开发了一种获得有价值的3-芳基喹喔啉-2(1 H)-酮的通用方法。作为替代能源,在超声辐射下仅需10分钟即可进行反应,仅提供水作为副产物。通过该原子有效方案,以良好至优异的产率选择性地获得了总共二十三种不同的3-芳基喹喔啉-2(1 H)-。另外,使用1 H– 15 N HMBC实验来揭示所得产物的区域异构现象。
Visible-light-induced, copper(i)-catalysed C-N coupling between o-phenylenediamine and terminal alkynes: one-pot synthesis of 3-phenyl-2-hydroxy-quinoxalines
and terminal acetylenes was performed using simple copper(I) chloride as a catalyst for the synthesis of quinoxaline derivatives. The current method works well for a wide range of electron rich as well as electron poor group-substituted o-phenylenediamines and phenylacetylenes. The key component in the reaction is the direct photo-excitation of in situ generated copper arylacetylide (λabs = 420–480 nm)
Aqueous Hydrofluoric Acid Catalyzed Facile Synthesis of 2,3,6-Substituted Quinoxalines
作者:A. Chandra Shekhar、A. Ravi Kumar、G. Sathaiah、K. Raju、P. V. S. S. Srinivas、P. Shanthan Rao、B. Narsaiah
DOI:10.1002/jhet.1753
日期:2014.9
A versatile synthetic route for the preparation of 2,3,6‐trisubstituted quinoxalines in excellent yield is developed from θ‐diamines and 1,2‐dicarbonyl compounds in which aqueoushydrofluoricacid was employed as the medium and catalyst. Other salient features of this protocol include milder conditions, absence of coupling agents, and easy workup procedures.