Novel synthesis of a series of spiro 1,3-indanedione-fused dihydropyridines through the condensation of a tetrone with N-aryl/alkylenamines in presence of solid support silica sulfuric acid

A convenient protocol for the library synthesis of biologically important 1-aryl-,6-spiro(,-indanedione)--indeno[1,2-]quinoline-5,7-diones has been developed. In this one-pot reaction protocol a tetrone is condensed with various -aryl/alkylenamines of 1,3-cyclohexadiones on the surface of a solid-supported acid catalyst silica sulfuric acid under solvent-free condition. The significant advantages of this methodology are the use of solvent-free reaction conditions, operational simplicity of the reaction, good yield of the products with high atom economy, and employment of a recyclable catalyst. All these favorable factors make the present method convenient, economic, and 'benign by design'. Novel synthesis of a series of spiro 1,3-indanedione-fused dihydropyridines through the condensation of a tetrone with -aryl/alkylenamines in presence of solid support silica sulfuric acid. [GRAPHICS]