A chemoselective Ugi-type reaction in water using TMSCN as a functional isonitrile equivalent: generation of heteroaromatic molecular diversityElectronic supplementary information (ESI) available: Spectra of compounds (4a-r; 7a-f). See DOI: 10.1039/c2ob26733k

KF-mediated nucleophilic activation of TMSCN as a functional isonitrile equivalent establishes an efficient and chemoselective Ugi-type multicomponent reaction of a heterocyclic amidine and aldehyde with TMSCN in water. In this approach, the use of isocyanide is circumvented, known competing reactions are virtually eliminated, pure products are obtained by a non-chromatographic method, and therapeutically relevant and diverse N-fused 3-aminoimidazoles can be prepared from a wide variety of aldehydes and heterocyclic amidines. This reaction coupling with cascade cyclization provides various privileged tetracyclic heteroaromatic scaffolds. KF-mediated nucleophilic activation of TMSCN as a functional isonitrile equivalent establishes an efficient and chemoselective Ugi-type multicomponent reaction of a heterocyclic amidine and aldehyde with TMSCN in water.