Synthesis of Double Benzimidazole‐Fused Quinazolines and Pyrimidines Catalyzed by Recyclable Magnetic Cu‐MOF‐74

Abstract 2‐(2‐Bromoaryl)‐ and 2‐(2‐bromovinyl)benzimidazoles are combined and cyclized with benzimidazoles using a catalytic amount of magnetic Cu‐MOF‐74 (Fe 3 O 4 @SiO 2 @Cu‐MOF‐74) and a base under O 2 atmosphere, yielding the corresponding double benzimidazole‐fused quinazolines and pyrimidines. The catalyst can be recovered using a magnetic bar and reused multiple times without significant loss of catalytic activity. The reaction mechanism likely involves the initial formation of a C−N coupled intermediate through nucleophilic aromatic substitution, followed by oxidative cyclization.