Insights in the Synthesis of Imidazolones from Aldehydes, Isocyanides, or Oxazolines.

α-Isocyanoacetamide derivatives were first converted to oxazolines under newly developed conditions. These oxazolines were used as precursors of α-isocyanoacrylamides, which could lead to various 2-arylated imidazolones. In addition, it was shown that both oxazolines and their precursors could efficiently lead to imidazolones unsubstituted at C2 in a very rapid, one-pot transformation, thus paving the way toward unprecedented routes to imidazolones, having a good tolerance to different substitution patterns.