Synthesis of Benzimidazolones via One-Pot Reaction of Hydroxylamines, Aldehydes, and Trimethylsilyl Cyanide Promoted by Diacetoxyiodobenzene

A novel and efficient PhI­(OAc)2-promoted one-pot reaction
of aromatic hydroxylamines, aldehydes, and TMSCN in the presence of
BF3·Et2O is described. A wide variety of N-substituted benzimidazolones are obtained with satisfactory
yields under mild reaction conditions. The method was proven to be
efficient for the synthesis of benzimidazolone derivatives from readily
available starting materials.