Metal‐Free Synthesis of 3‐Arylquinolin‐2‐ones from N,2‐Diaryl‐ acrylamides via Phenyliodine(III) Bis(2,2‐dimethylpropanoate)‐ Mediated Direct Oxidative C−C Bond Formation
Treatment of N,2‐diarylacrylamides with the organoiodine(III) compound phenyliodine(III) bis(2,2‐dimethylpropanoate) [PhI(O2C‐t‐Bu)2] and boron trifluoride etherate (BF3⋅Et2O) resulted in a direct and selective oxidative C(sp2)−C(sp2) bond formation leading to a convenient assemblage, under mild conditions, of the biologically important 3‐arylquinolin‐2‐one skeleton. Differing from the five‐membered oxindole products from oxidative cyclizations mediated by transition metals, this metal‐free approach realized a direct annulation of the N‐arylacrylamide into a six‐membered 3‐arylquinolin‐2‐one skeleton.
