A microwave‐assisted synthetic approach to analyzing disubstituted pyrrolo[2,3‐d]pyrimidine diversity via ligand‐free Cu‐catalyzed N‐arylation.

Facile introduction of diverse substituents to 2‐ or 4‐chloro‐7H‐pyrrolo[2,3‐d]pyrimidines was examined with microwave‐assisted nucleophilic substitution and Cu‐catalyzed N‐arylation. Microwave‐assisted Cu‐catalyzed N‐arylation of pyrrolo[2,3‐d]pyrimidines with various nucleophiles proceeded very well with diverse heteroaryl halides. Sequential microwave‐assisted substitution provided good to excellent yields of 2,7‐ or 4,7‐disubstituted pyrrolo[2,3‐d]pyrimidines, with short reaction times and energy savings compared with conventional thermal heating. The diverse pyrrolo[2,3‐d]pyrimidine derivatives are useful for screening drug candidates for various diseases. [ABSTRACT FROM AUTHOR]