Isocyanide-based multicomponent reactions: synthesis of 2-(1-(alkylcarbamoyl)-2,2-dicyanoethyl)-N-alkylbenzamide and 1,7-diazaspiro[4,4]nonane-2,4-dione derivatives

A four-component reaction between 2-formylbenzoic acid, malononitrile, isocyanides, and primary alkyl amines has been developed for an efficient preparation of 2-(1-(alkylcarbamoyl)-2,2-dicyanoethyl)-N-alkylbenzamide and 1,7-diazaspiro[4,4]nonane-2,6-dione derivatives under two different conditions. It is shown that simply by changing the reaction solvent from ethanol to dichloromethane and controlling the order of the addition of reagents, two completely different products can be obtained. These multicomponent reactions showed high atom economy.