A Novel One-Pot Three-(<i>in Situ</i> Five-)Component Condensation Reaction: An Unexpected Approach for the Synthesis of Tetrahydro-2,4-dioxo-1<i>H</i>-benzo[<i>b</i>][1,5]diazepine-3-yl-2-methylpropanamide Derivatives

A novel and efficient method has been developed for the synthesis of tetrahydro-2,4-dioxo-1H-benzo[b][1,5]diazepine-3-yl-2-methylpropanamide derivatives using an aromatic diamine, Meldrum’s acid, and an isocyanide in CH2Cl2 at ambient temperature in high yields without using any catalyst or activation. The procedure provides an alternative method for the synthesis of benzo[b][1,5]diazepine derivatives. These compounds have closely related ring systems such as triflubazam, clobazam, and 1,5-benzodiazepines, which have a broad spectrum of biological activities.