Gold Nanoparticle-Catalyzed Multicomponent Reactions

Abstract

Nanotechnology and nanoscience hold great promise for many multidisciplinary applications, including catalysis where gold nanoparticles (GNPs) are considered "safer and environmentally benign" on account of the fact that they are relatively nontoxic and efficient for pivotal applications in natural-product synthesis, organic reactions, pharmaceutical industry, and medicinal chemistry. Since the physicochemical characteristics of GNPs pertain to their shape, size, composition, and surface modification, these features contribute to the reactivity and toxicity of nanomaterials in the catalytic systems. Multicomponent reactions (MCRs) lead to expeditious synthesis of biologically active molecules and active pharmaceutical ingredients (APIs) with atom economy and high efficiency, as well as a low E-factor, and they can be performed in one-pot operations deploying three or more reactants. Thus, applications of GNPs as robust catalysts in MCRs comprise an effective synthetic route with an ideal combination for the augmentation of greener and sustainable methods. Accordingly, cutting-edge examples of gold nanoparticle-catalyzed multicomponent reactions leading to a diverse range of valuable organic molecules such as isoxazolines, propargylamines, 3,4dihydropyrimidin-2(1H)-ones, pyrans, chromeno[2,3-d]pyrimidins, pyridines, and benzodiazepines are discussed and highlighted.

Six‐Component Reactions and Beyond: The Nuts and Bolts

“…In addition to the Ugi reaction, a battery of MCRs are available in the tool box of the modern day chemist namely Petasis, Povarov and Groebke‐Blackburn‐Bienaymé reactions to name but a few [44–46] . Indeed, it must be noted that the discovery of each new MCR often spawns efforts from prominent chemists drawn on these named reactions to shorten and create a novel synthetic routes [47–52] . Shown in Figure 1 is various types of well‐known named MCRs.…”

“…[44][45][46] Indeed, it must be noted that the discovery of each new MCR often spawns efforts from prominent chemists drawn on these named reactions to shorten and create a novel synthetic routes. [47][48][49][50][51][52] Shown in Figure 1 is various types of well-known named MCRs.…”

Covalent organic frameworks and multicomponent reactions: an endearing give-and-take relationship

“…31 In this setting, MCRs are performed with three or more accessible starting reagents in one vessel, resulting in the preparation of complex scaffolds without separation and purification of the involved intermediates. 32 In contrast to traditional "stop-and-go" synthesis, these kinds of organic reactions enjoy numerous green aspects namely a high degree of atom economy, step and bond efficiency, easy workup procedures, operational friendliness, green and sustainable media, reduced pollution, time-effective transformations, and often satisfactory yields of the final products. 33 According to green chemistry principles, reducing the number of reaction steps via a one-pot synthetic route is an immense inherent advantage of MCRs; "one-pot" reactions conducted in a single reaction vessel often translate to remarkable efficiencies along with waste diminution.…”

Metal‐Free, Biomass‐Derived Nano‐Architectured Carbon Quantum Dots as an Efficient Acid‐Base Bifunctional Catalyst for Facile Synthesis of Benzo[g]chromene and Pyrimidine Analogs

“…bonds in sustainable fashion [5] . These MCRs are extensively used to synthesize biologically important complex heterocyclic compounds (HCs) in a simple, selective and atom economical manner [6,7] . The MCR which involves the condensation of carbonyl compounds is a common strategy to construct chemical entities.…”

“…[5] These MCRs are extensively used to synthesize biologically important complex heterocyclic compounds (HCs) in a simple, selective and atom economical manner. [6,7] The MCR which involves the condensation of carbonyl compounds is a common strategy to construct chemical entities. The basic reactions involved in carbonyl based MCRs include Knoevenagel condensation, [8] Michael addition [9] and intramolecular cyclization [10] etc.…”