Síntesis de iononas por ciclizacion de pseudoionona empleando catalizadores sólidos ácidos

V.K. DÍEZ; C.R. APESTEGUÍA; J.I. DI COSIMO

Buenos Aires

Congreso; XVI Congreso Argentino de Catálisis; 2009

Ionone synthesis (a, b and g isomers) by pseudoionone cyclization was studied on zeolite HBEA, Amberlyst 35W resin, SiO2-Al2O3, unsupported and silica-supported heteropolyacids (HPA/SiO2) and Cs-HPA salt. Amberlyst 35W and HPA/SiO2 were the most active catalysts, suggesting that the PS conversion is promoted on strong Brønsted acid sites. Particularly, a 79 % ionone yield was obtained on 58.5 wt. % HPA/SiO2 after 1.5 h of reaction at 383 K and 250 kPa. This value is similar to the best yields reported for the homogeneously-catalyzed reaction using sulfuric acid. Always, the three iononeisomers were obtained but the ionone isomer distribution significantly changes with PS conversion and reaction time and temperature.a, b and g isomers) by pseudoionone cyclization was studied on zeolite HBEA, Amberlyst 35W resin, SiO2-Al2O3, unsupported and silica-supported heteropolyacids (HPA/SiO2) and Cs-HPA salt. Amberlyst 35W and HPA/SiO2 were the most active catalysts, suggesting that the PS conversion is promoted on strong Brønsted acid sites. Particularly, a 79 % ionone yield was obtained on 58.5 wt. % HPA/SiO2 after 1.5 h of reaction at 383 K and 250 kPa. This value is similar to the best yields reported for the homogeneously-catalyzed reaction using sulfuric acid. Always, the three iononeisomers were obtained but the ionone isomer distribution significantly changes with PS conversion and reaction time and temperature.