Aluminosilicates with Different Porous Structures in the Synthesis of 2-Ethyl-3-Methylquinoline

Resumo

The catalytic properties of microporous zeolites of different structural types (FAU, BEA, MOR, and MFI), a micro–meso–macroporous zeolite (H-Ymmm), and an ASM mesoporous aluminosilicate in the reaction of aniline with propionic aldehyde have been studied. It has been found that the reaction proceeds with a high conversion of aniline (90–99% over zeolites and 71% over an ASM aluminosilicate) to form two main products, namely, 2-ethyl-3-methylquinoline (2) and 2-ethyl-3-methyl-N-phenyl-1,2,3,4-tetrahydroquinoline-4-amine (3). The most selective catalysts for the synthesis of quinoline 2 are H-Y (up to 64%) and H-Ymmm (59%) zeolites and the ASM aluminosilicate (50%). It has been shown that an increase in the quinoline 2 selectivity is promoted by an increase in the catalyst acidity, in the reaction temperature to 160°C, in the catalyst concentration to 20 wt %, and in the aniline : aldehyde molar ratio to 1 : 2.