CENTRO DE INVESTIGACION Y DESARROLLO EN CIENCIAS APLICADAS "DR. JORGE J. RONCO"
Unidad Ejecutora - UE
Tungstophosphoric acid supported on zirconia: A recyclable catalyst for the green synthesis on quinoxaline derivatives under solvent-free conditions
ALEXIS SOSA; TOA RIVERA; MIRTA N. BLANCO; LUIS R. PIZZIO; GUSTAVO P. ROMANELLI
PHOSPHORUS SULFUR AND SILICON AND THE RELATED ELEMENTS
TAYLOR & FRANCIS LTD
Lugar: Londres; Año: 2012
A green, simple and fast procedure has been developed for the preparation of quinoxaline derivatives by a condensation of 1,2-diamines, 1,2-dicarbonyl compounds, in the presence of zirconium oxide modified with tungstophosphoric acid (H3PW12O40) as a heterogeneous catalyst, in a solvent-free medium using conventional heating. Quinoxaline derivatives were formed in short time periods and excellent yields (65-100%). The reaction work-up is very simple and the catalyst can be easily separated from the reaction mixture and reused several times in subsequent reactions without appreciable loss of the catalytic activity.