Late Stage CH Activation of a Privileged Scaffold; Synthesis of a Library of Benzodiazepines

A library of over twenty 5‐(2‐arylphenyl)‐1,3‐dihydro‐2H‐1,4‐benzodiazepin‐2‐ones has been formed by a microwave‐mediated late‐stage palladium‐catalysed arylation of 1,4‐benzodiazepines using diaryliodonium salts. This can also be applied to nordazepam (7‐chloro‐5‐phenyl‐1,3‐dihydro‐2H‐1,4‐benzodiazepin‐2‐one), the active metabolite of diazepam, and subsequent N‐alkylation and/or H/D exchange allows further diversification towards elaborated pharmaceuticals and their 3,3′‐deuterated analogues. magnified image