Rapid multistep synthesis of 1,2,4-oxadiazoles in a single continuous microreactor sequence.

A general method for the synthesis of bis-substituted 1,2,4-oxadiazoles from readily available arylnitriles and activated carbonyls in a single continuous microreactor sequence is described. The synthesis incorporates three sequential microreactors to produce 1,2,4-oxadiazoles in approximately 30 min in quantities (40-80 mg) sufficient for full characterization and rapid library supply.