Ligand-free palladium assisted insertion of isocyanides to urea derivatives for cascade synthesis of phenylamino-substituted quinazolinones

Palladium catalyzed cascade coupling of substituted urea derivatives and tert-butyl isocyanide for the efficient synthesis of phenylamino-substituted quinazolinones has been developed in moderate to good yields. This method provides a short and alternative approach for the synthesis of quinazolinones derivatives which are valuable compounds with biological and pharmacological potentials. A plausible mechanistic scheme is proposed.