Synthesis of bis- and trisoxazole derivatives via Suzuki-Miyaura cross-coupling reaction and van Leusen oxazole synthesis

Both C-2- and C-3-symmetric oxazole derivatives are synthesized via the Suzuki-Miyaura cross-coupling and van Leusen oxazole synthesis. Here, bis- and triscarboxaldehydes were obtained via the Suzuki-Miyaura cross-coupling and further treated with p-toluenesulfonylmethyl isocyanide (TosMIC) in the presence of potassium carbonate as a base and methanol as a solvent to deliver the corresponding oxazole derivatives.