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Perspective on the Advancements in Conjugated Polymer Synthesis, Design, and Functionality over the Past Ten Years
Published in John R. Reynolds, Barry C. Thompson, Terje A. Skotheim, Conjugated Polymers, 2019
Brian Schmatz, Robert M. Pankow, Barry C. Thompson, John R. Reynolds
Another methodology akin to click-chemistry includes multi-component reactions. These reactions may not possess all of the highly regarded merits that would qualify them to be click-reactions, e.g. environmentally benign conditions, simple-purifications, and high yields, but the potential of these reactions to construct conjugated polymers from new building blocks opens an exciting door leading to a new realm of conjugated polymer chemistry and structure.[67] Also, this methodology seeks to incorporate simpler building blocks, allowing for streamlined synthetic pathways, and ultimately trimming down the amount of waste and time associated with a lengthy monomer synthesis. Shown in Figure 3.30C with polymers 111 and 112, Arndtsen et al. prepared fluorene and pyrrole copolymers with different π-spacers, such as thiophene and naphthalene.[67c] The polymerization proceeds through the preparation of poly(1,3-dipoles), which then undergoes cycloaddition reactions with an alkyne. This procedure allowed for the preparation of polymers with yields up to 98% and Mn up to 40.7 kDa.
N-Heterocycles
Published in Navjeet Kaur, Metals and Non-Metals, 2020
Various multi-component reactions have explored and increased the diversity of compounds and reaction speeds. For macrocyclization of linear peptides, aziridine aldehyde dimers have been utilized in the multi-component Ugi reaction. Zinc acetate-catalyzed multi-component aldehyde-amine-alkyne couplings with aziridine aldehydes have been investigated for the synthesis of densely functionalized propargyl amino aziridines in good yields and with upto 20:1 diastereoselectivity (Scheme 109) [277].
Microwave-Assisted Transition Metal-Catalyzed Synthesis of Pharmaceutically Important Heterocycles
Published in Banik Bimal Krishna, Bandyopadhyay Debasish, Advances in Microwave Chemistry, 2018
Dipti Shukla, Priyank Purohit, Asit K. Chakraborti
The multicomponent reactions (MCRs) have been recognized as new tools of synthetic organic/medicinal chemists due to their multifold advantages: high atom economy, applicability in the construction of complex structural features from simple and readily available substrates in one-pot, etc. [28]. Thus, the strategy of MCRs is extended for the synthesis of various organic compounds [29–33], which find applications in the generation of new anti-leishmanial agents [34], as important building blocks, and in the construction of bioactive heterocycles [35–38].
Iron-promoted sulfur sequestration for the substituent-dependent regioselective synthesis of tetrazoles and guanidines
Published in Journal of Sulfur Chemistry, 2021
Venkata Bhavanarushi Pendem, Ramana Tamminana, Madhavi Nannapaneni
The conversion of a simple substrate into diverse libraries of more complex molecules constitutes a great challenge in modern organic synthesis from both academic and industrial standpoints [1,2]. Recently, multicomponent reactions have emerged as important synthetic approaches involving at least three or more than three variable components participating in such a way that to provide a single product [3–9]. Multicomponent reactions provide a valuable and convenient methodology to create several natural, bioactive, and non-bioactive organic molecules. Over the past few decades, these MCRs have had a significant impact due to their huge advantages such as speed, efficiency, green reaction conditions, and atom economy. Based on the better productivity and considerable process time reduction of MCRs compared to the classical techniques, MCRs have become popular in organic chemistry [10–15].
Synthesis of one-pot pyrazolo[4′,3′:5,6]pyrano[2,3-c]phenazin-15-yl) methanone derivatives via a multi-component using Fe3O4@TiO2-SO3H as a recoverable magnetic catalyst under microwave irradiation
Published in Green Chemistry Letters and Reviews, 2020
One of the ideal synthesis methods is the use of monovalent multivariate reactions, which has received much attention in recent decades (1). One of the methods of synthesizing organic compounds is the use of one-pot multiplets reactions, and since these reactions have advantages such as ease of application and high speed in the process, they have received much attention in the synthesis of organic chemistry. For this reason, the design of new multi-component reactions has attracted the attention of scientists and pharmacists (2–4). Phenazine derivatives are a group of organic compounds that are of particular importance due to their desirable properties in various fields such as pharmacy, gel manufacturing, ion-electrode fabrication and in the isolation of some compounds. Since these compounds are often made from complex, multi-step synthesis, it is important to find a quick and easy method for their synthesis (5,6). This method allows for the fabrication of complex and diverse molecules by the easy formation of several new covalent bonds in a single-valence conversion, which is quite close to the ideal synthesis concept (7–9).
Sonochemical synthesis of methyl-4-(hetero)arylmethylene isoxazole-5(4H)-ones using SnII-montmorillonite
Published in Green Chemistry Letters and Reviews, 2018
Majid Ahmadzadeh, Zohre Zarnegar, Javad Safari
One-pot multicomponent reactions have recently been discovered to be a powerful synthetic tool for the synthesis of heterocyclic compounds, since the products are formed in one-pot and the diversity can be achieved simply by varying each component. The simplicity of a one-pot procedure, the possible structural variations, the atom economy and convergent character, operational simplicity and the very large number of accessible organic compounds are among the described advantages of multicomponent reactions (1, 2). One such multicomponent reaction that belongs to the latter category is the isoxazole derivatives synthesis.