Synthesis of 1‐Aryl Isoquinolinones or o‐Diaryl Pyrimidines via Bismuth Triflate‐Mediated Intermolecular Annulation of Arylacetic Acids with Nitroarylaldehydes or Trimethoxybenzene in the Presence of Acetonitrile

In this article, bismuth triflate (Bi(OTf)3)‐controlled intermolecular multi‐component condensation of oxygenated arylacetic acids with electron‐withdrawing nitroarylaldehydes or electron‐donating trimethoxybenzene provide 1‐aryl isoquinolinones or o‐diaryl pyrimidines in acetonitrile at 60 °C. The uses of various metal triflates and reaction conditions are investigated in the one‐pot reaction. Only water is generated as the byproduct via (4C+1C+1N) and (2C+1N1C+1N1C) annulation routes. Plausible mechanisms have been proposed.