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

Abstract

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.

Multicomponent Reaction-Assisted Drug Discovery: A Time- and Cost-Effective Green Approach Speeding Up Identification and Optimization of Anticancer Drugs

“…Even though the classical IMCRs are not suited for generating heterocyclic compounds, new variations of the Passerini three-component reaction [ 48 , 57 ], Ugi three- and four-component reaction (U-4CR) [ 58 , 59 ], van Leusen reaction [ 60 ] and Groebke–Blackburn–Bienaymé reaction (GBBR) [ 61 , 62 , 63 , 64 ] have been explored and, indeed, IMCRs are leading today’s MCR chemistry [ 65 ]. For further information on isocyanide chemistry, the reader is directed toward further comprehensive review articles from Prof. Heravi’s group [ 66 , 67 , 68 , 69 , 70 ], Prof. Dömling’s group [ 71 , 72 , 73 , 74 , 75 , 76 , 77 , 78 , 79 , 80 , 81 , 82 ] and other extensive publications [ 83 , 84 , 85 , 86 , 87 , 88 , 89 , 90 , 91 , 92 , 93 , 94 , 95 ].…”