Isocyanide-based Cascade Reactions in the Synthesis of Aza-heterocycles: A Marriage of Convenience

Background: The design and performing of cascade reactions is a challenging but stimulating and interesting facet of organic synthesis, yet one that can convey conspicuous novelty, efficiency as well as elegance and sophistication to synthetic approaches. On the other hand, isocyanides are well-recognized as privileged synthons in the synthesis of a wide range of heterocycles. Objective: In this review, we try to illustrate the power, efficiency, and convenience of combining cascade process as an expedient strategy with versatility of isocyanide-based multicomponent reactions in the synthesis of aza-heterocycles from 1993 till date. Comprising isocyanides in cascade or sequential pathway also represents a milestone in combinatorial chemistry which is a bounce for this contented marriage.