Heterocycles as Key Substrates in Multicomponent Reactions: The Fast Lane towards Molecular Complexity

Abstract

Heterocycles display an intrinsic reactivity which enables rich, versatile and productive transformations. Taking into account their ubiquitous presence in natural products and drugs, the development of new, fast and efficient preparative protocols for these structures remains an urgent task in Organic Synthesis. Multicomponent reactions using heterocyclic chemistry offer new possibilities to exploit this exclusive reactivity. Recent results show relevant examples of such transformations. Several approaches which allow the construction of complex heterocyclic compounds from simple starting materials using this principle have been analyzed.

An efficient protocol for the synthesis of N-fused 2, 5-diketopiperazine via base catalyzed Ugi-type MCR

“…Ugi type reaction is not only used for biological screening in medicinal chemistry but also used for synthesis of drug molecule or drug intermediate as well. 6 The post functionalization of MCR [7][8][9][10][11] adducts has received considerable attention in recent years. Because of its combination with various post-transformations, typically cyclization, provides a fast and efficient entry to libraries of diverse heterocyclic scaffolds.…”

Transition Metal‐Catalyzed Synthesis of Monocyclic Five‐Membered Aromatic Heterocycles

“…A subsequent 5-endo-dig cyclization afforded a variety of 1,2,3,5-tetrasubstituted and even 1,2-fused pyrroles in moderate to good yields. 8 In their recent study, Scheidt and coworkers devised the Rh(II)-catalyzed methodology employing imines, activated alkynes and diazoacetonitrile (DAN) in a convergent three-component 2 þ 2 þ 1 assembly reaction leading to pyrrolo-3,4-dicarboxylates 359 in moderate to high yields (Scheme 8.124) [317]. The authors proposed that DAN reacts with the Rh(II) catalyst to generate the corresponding metallocarbenoid 360.…”

“…Other examples of practical applications of furans and pyrroles include dyes, polymers, and electronic materials [4]. Moreover, these heterocycles are employed as important intermediates in organic synthesis [5][6][7][8][9]. The successful application of furans and pyrroles in these and many other ways and their significance in applied and fundamental areas have placed them at the forefront of contemporary organic chemistry.…”

Contemporary development in sequential Knoevenagel, Michael addition multicomponent reaction for the synthesis of 4-Aryl-5-oxo-5H-indeno[1,2-b]pyridine-3-carbonitrile

“…In the current literature of synthetic chemistry, multicomponent reactions (MCRs) gained an impressive position in the synthesis of a variety of organic compounds [1][2][3]. The MCRs involve one-pot transformations and formation of new C-C or Chetero atom bonds, which are the structural backbone of heterocyclic molecules [4][5][6].…”