Isocyanide-based Multicomponent Reactions

This intriguing title of a paper refers to a method of making isocyanides “in-situ” and then reacting further in standard multicomponent reactions such as Ugi and Passerini. The isocyanides are generated by reacting benzyl or allylic halides with potassium cyanide in the presence of silver and a phase transfer catalyst in NMP, or using potassium ferrocyanide / PTC, though reactions are slow (110 oC, 24 h). For the combined Ugi-Smiles coupling, reactions are carried out in MeCN at 80 oC. (El Kain l et al., Syn Lett., 2009 (9), 1401.