Solid-phase synthesis of quinoxalines on SynPhase™ Lanterns

A convenient and straightforward solid-phase synthesis of quinoxalines is described. A polymer-bound o-phenylenediamine was reacted with α-bromoketones in DMF at 60°C to give quinoxalines in good purity and yield after TFA cleavage. The quinoxalines were presumably formed via an initial nucleophilic substitution, followed by subsequent cyclization–oxidation. A small library of ten quinoxalines was prepared on SynPhase™ Lanterns using this simple one-pot procedure.