Biomass into chemicals: One-pot two- and three-step synthesis of quinoxalines from biomass-derived glycols and 1,2-dinitrobenzene derivatives using supported gold nanoparticles as catalysts

Abstract

ElsevierCliment Olmedo, MJ.; Corma Canós, A.; Hernández, JC.; Hungría, AB.; Iborra Chornet, S.; Martínez Silvestre, S. (2012). Biomass into chemicals: One-pot two-and three-step synthesis of quinoxalines from biomass-derived glycols and 1,2-dinitrobenzene derivatives using supported gold nanoparticles as catalysts. AbstractAn efficient and selective one-pot two steps, method for the synthesis of quinoxalines by oxidative coupling of vicinal diols with 1,2-phenylenediamine derivatives, has been developed by using gold nanoparticles supported on nanoparticulated ceria (Au/CeO 2 ) or hydrotalcite (Au/HT) as catalysts and air as oxidant, in absence of any homogeneous base. Reaction kinetics shows that the reaction controlling step is the oxidation of the diol to α-hydroxycarbonyl compound.Furthermore, a one-pot three steps synthesis of 2-methylquinoxaline starting from 1,2-dinitrobenzene and 1,2-propanediol has been successfully carried out with 98% conversion and 83% global yield to the final product.

Gold Catalysis Opens Up a New Route for the Synthesis of Benzimidazoylquinoxaline Derivatives from Biomass‐Derived Products (Glycerol)

“…For the reuse, the recovered catalyst was used in a subsequent run as described in the Experimental Section. According to our previous results for the synthesis of quinoxalines, [18] no leached gold species were detected in the reaction media, whereas the gold content in the used catalyst, as measured by X-ray fluorescence, remained the same after each run. Nevertheless, some catalyst deactivation was observed (Figure 3).…”

“…Thus, the reaction between 1,2-phenylenediamine (1 a) and glycerol (2) was performed with and without Au/CeO 2 as a catalyst in diglyme as a solvent at 140 8C. As we have shown previously, [18] this solvent was able to dissolve completely both reactants (polyols and 1,2-phenylenediamine derivatives) and products and alScheme 1. Benzimidazoylquinoxaline synthesis routes according to Refs.…”

“…[18,19] Catalyst optimization studies showed that Au nanoparticles supported on nanosized CeO 2 (Au/CeO 2 ) were the most active and selective catalysts to obtain quinoxalines. The influence of the support on the rate of the alcohol oxidation by gold has been ascribed to changes produced on the crystallite shape as well as to the participation of the support in the catalytic cycle.…”

“…The same trend has been described in the literature for the reaction between a-hydroxycarbonyl compounds and 1,2-phenylenediamine derivatives. [18,22] …”

Funcionalização dirigida de quinoxalinas visando à preparação de substâncias bioativas

“…Nos últimos anos, reações utilizando metais tem sido bastante exploradas na síntese de compostos orgânicos (HARTWIG, 1998;EICHAMAN;STAMBULI, 2011;CLIMENTA et al, 2012). Yu e colaboradores (2015) propuseram a síntese de quinoxalinas utilizando Cu(OAc)2•H2O como catalisador do processo oxidativo da deoxibenzoínas à 1,2-dicetonas.…”