GREEN PROTOCOL FOR THE FRIEDLANDER SYNTHESIS: KAl(SO4)2·12H2O-SiO2 (ALUM-SiO2) A HIGHLY EFFICIENT CATALYST IN THE SYNTHESIS OF QUINOLINES

摘要

In this letter, an efficient synthesis of an array of poly-substituted quinolines from 2-aminoaryl ketones and β-ketoester, β-diketones and α-methylene ketones using KAl(SO4)2·12H2O-SiO2 (Alum-SiO2) under solvent-free conditions is described. Compared with the classical Friedlander synthesis this new synthetic method has the advantage of excellent yields (90-98%), shorter reaction time, and reusability of the catalyst.