An efficient synthesis of quinoxalines catalyzed by monoammonium salt of 12-tungstophosphoric acid

Quinoxaline, its derivatives and applications: A State of the Art review

“…Molecular weight of the quinoxaline is 130. 15, with a molecular formula of C 8 H 6 N 2 , and it is a white crystalline powder, at standard conditions [1].…”

“…Numerous methods are available for the synthesis of quinoxaline derivatives which involve condensation of 1,2-diamines with a-diketones [13], 1,4-addition of 1,2-diamines to diazenylbutenes [14], cyclizationeoxidation of phenacyl bromides [15] and oxidative coupling of epoxides with ene-1,2-diamines [16]. Recent research groups have presented reports concerning the synthesis of different quinoxaline derivatives involving several green methodologies, including recyclable catalysts, microwave-assisted synthesis and reactions in aqueous medium [17].…”

Synthesis, Characterization and Thermal Study of New Transition MEtal Complexes Derived from 3-Acetylcoumarine

“…The ligands L 1 and L 2 exhibited similar spectral features in the UV-Vis region with bands around 255, 310 and 440 nmrespectively. The first band below 310 nm is assigned to a ligand transition (n-π*) and(π-π*) [10,14] .The other two bands, 370 and 440 nm are attributed to charge transfer processes. The visible spectra of all the complexes are similar and show an intense absorption band near ~360 nm and moderately intense shoulder band near 395-415 nm and distinct band at ~656 nm.…”

“…The Schiff bases of coumarins comprise a very large class of Lewis bases that have interested in the field of coordination chemistry [8]. The antimicrobial activity of coumarin nucleus and related derivatives [9] has a great important effects like antibacterial, antithromboticandvasodilators [10].As it hasinvestigated in the literature the biological activity of some coumarinderivatives significantly enhances by binding to metal ions [11,12]. In continuation with this interest of cumarine chelates, we report the synthesis, characterization and thermal study of some first row transition metal complexes with two ligands derived from 3-bromoacetyl-cumarine-2-one.…”

A green approach toward quinoxalines and bis-quinoxalines and their biological evaluation against A431, human skin cancer cell lines

“…Consequently, many methods for the synthesis of diversely substituted quinoxalines have been reported that utilize a number of catalysts, solvents and methodologies. For example, some recent reports discuss the catalytic use of gold nanoparticles [21], CuCl 2 [22], AgI [23,24], Ga(ClO 4 ) 3 [25], DABCO [26], H 3 PW 12 O 40 /MCM-41 nanoparticles [27], monoammonium salt of 12-tungstophosphoric acid [28], PdCl 2 [29], CeCl 3 .7H 2 O [30] and silica nanoparticles [31]. They also report the use of solvents such as glycerol [32] and PEG-400 [33,34], and methodology such as dehydrogenative coupling using molecular oxygen as an oxidant [35].…”