DPO and POPOP carboxylate-analog sensors by sequential palladium-catalysed direct arylation of oxazole-4-carboxylates

Sequential palladium-catalysed direct (het)arylation of oxazole-4-carboxylates is achieved to give rapid access to DPO and POPOP (di)carboxylate-analogs. Three novel DPO- and POPOP-type sensors with unusual Stokes shifts and high quantum yields are discovered.