Pd/C Catalyzed Cascade Synthesis of 2‐Arylquinazolinones from 2‐Iodoacetanilides Employing Ammonia and CO Precursors

Abstract

Abstract An efficient and straightforward approach has been demonstrated for 2‐aryl quinazolinones synthesis from 2‐iodoacetanilides using ammonium carbamate/ammonium carbonate and oxalic acid under heterogeneous Pd/C catalyzed conditions. Herein, we have carried out the reactions employing oxalic acid and ammonium carbamate or ammonium carbonate as two gaseous precursors i. e. CO and NH 3 respectively for the synthesis of desired quinazolinones in appreciable yields. The protocol followed cascade aminocarbonylation and cyclization under optimized reaction conditions. The protocol exhibited wide functional group tolerance under set reaction conditions and delivered the respective 2‐aryl quinazolinones with great diversity. The heterogeneous Pd/C catalyst was found to be recyclable up to four consecutive runs without significant decrease in catalytic activity.