Synthesis of 8-heteroaryl nitroxoline analogues via one-pot sequential Pd-catalyzed coupling reactions.

A series of 8-heteroaryl substituted quinolines were prepared, either by direct C-H arylation of five-membered heteroarenes, or Pd-catalyzed coupling of organoboron reagents with bromoquinolines. The use of (benzo)thiophenyl or (benzo)furanyl boron coupling partners allowed further C-H functionalization on the five-membered heteroaryl ring with aryl bromides in one flask to access a variety of polyconjugated molecular architectures. The developed methodology represents a simple approach towards 8-arylated analogues of the biologically interesting nitroxoline core.