One-pot four-component synthesis of 2,5-dioxo-1,2,3,4,5,6,7,8-octahydroquinolines catalyzed by silica-based sulfonic acid

A series of 2,5-dioxo-1,2,3,4,5,6,7,8-octahydroquinolines were synthesized through a rapid one-pot four-component reaction in the presence of heterogeneous silica-based sulfonic acid (SiO2-Pr-SO3H) under solvent-free conditions.