Efficient One-Pot Research Articles

An efficient One-Pot synthesis of NaOCl mediated pyrazolopyrimidine derivatives

The discovery and success of sildenafil, widely recognized as Viagra™, represented a major progress in the treatment of erectile dysfunction (ED). Numerous approaches for synthesis of the Pyrazolo[4,3-d]pyrimidine-7-one ring have reported in the literature. However, those methods have several drawbacks, including high temperatures, low yields, the use of hazardous materials, specific oxidation protocols, long reaction times, multiple reaction steps, and expensive catalysts. To overcome these limitations, we present a simple, catalyst-free, and cost-effective one-pot synthesis of pyrazolopyrimidine derivatives with a high yield and lower reaction time using the inorganic reagent i.e., sodium hypochlorite (NaOCl). The reaction uses easily available starting materials such as 4- amino-1-methyl-3-propylpyrazole-5-carboxamide and aldehyde derivatives under moderate conditions, providing a greener alternative to typical multi-step synthesis techniques. Detailed optimization studies to afford pyrazolopyrimidine derivatives (6a-6o) show that NaOCl is a strong oxidizing agent that promotes cyclization and functionalization processes. Structures of synthesized compounds were confirmed by 1H NMR,13C NMR and HR-MS techniques.

One-Pot Tandem/Spirocyclization Reaction: Synthesis of Spiro[pyridine-thiazolidine] Ring Derivatives.

An efficient one-pot, three-component approach was devised to synthesize spiro[pyridine-thiazolidine] ring skeletons using thiazole salts, aldehydes, and enaminones. This method allows the assembly of structurally diverse spiroazepines through [3 + 1 + 2] tandem/spirocyclization reactions. This spirocyclization reaction offers several advantages, including transition metal-free conditions, high chemoselectivity, and the ability to construct structurally novel polycyclic compounds.

An Indium(III) Triflate Catalyzed Simple and Efficient One-Pot Synthesis of Substituted 3,3-Diaryloxindoles and Bis(indol-3-yl) methanes from Indoles and Isatins or Aryl Aldehydes

AbstractIndium(III) triflate was found to be an efficient metal catalyst for the electrophilic substitution reaction of substituted indoles with various isatins or aryl aldehydes in acetonitrile solvent to afford the corresponding 3,3-diaryloxindoles or bis(indol-3-yl)methanes, respectively, in high yields at room temperature. This new procedure has remarkable features such as experimental simplicity, high conversions, good to excellent yields, short reaction times, and simple workup procedures

Highly Efficient One-pot Electrosynthesis of Oxime Ethers from NOx over Ultrafine MgO Nanoparticles Derived from Mg-based Metal-Organic Frameworks.

Oxime ethers are attractive compounds in medicinal scaffolds due to the biological and pharmaceutical properties, however, the crucial and widespread step of industrial oxime formation using explosive hydroxylamine (NH2OH) is insecure and troublesome. Herein, we present a convenient method of oxime ether synthesis in a one-pot tandem electrochemical system using magnesium based metal-organic framework-derived magnesium oxide anchoring in self-supporting carbon nanofiber membrane catalyst (MgO-SCM), the in situ produced NH2OH from nitrogen oxides electrocatalytic reduction coupled with aldehyde to produce 4-cyanobenzaldoxime with a selectivity of 93 % and Faraday efficiency up to 65.1 %, which further reacted with benzyl bromide to directly give oxime ether precipitate with a purity of 97 % by convenient filtering separation. The high efficiency was attributed to the ultrafine MgO nanoparticles in MgO-SCM, effectively inhibiting hydrogen evolution reaction and accelerating the production of NH2OH, which rapidly attacked carbonyl of aldehydes to form oximes, but hardly crossed the hydrogenation barrier of forming amines, thus leading to a high yield of oxime ether when coupling benzyl bromide nucleophilic reaction. This work highlights the importance of kinetic control in complex electrosynthetic organonitrogen system and demonstrates a green and safe alternative method for synthesis of organic nitrogen drug molecules.

Efficient One-Pot Synthesis of Uridine Diphosphate Galactose Employing a Trienzyme System.

The limited availability of high-cost nucleotide sugars is a significant constraint on the application of their downstream products (glycosides and prebiotics) in the food or pharmaceutical industry. To better solve the problem, this study presented a one-pot approach for the biosynthesis of UDP-Gal using a thermophilic multienzyme system consisting of GalK, UGPase, and PPase. Under optimal conditions, a 2 h reaction resulted in a UTP conversion rate of 87.4%. In a fed-batch reaction with Gal/ATP = 20 mM:10 mM, UDP-Gal accumulated to 33.76 mM with a space-time yield (STY) of 6.36 g/L·h-1 after the second feeding. In repetitive batch synthesis, the average yield of UDP-Gal over 8 cycles reached 10.80 g/L with a very low biocatalyst loading of 0.002 genzymes/gproduct. Interestingly, Galk (Tth0595) could synthesize Gal-1P using ADP as a donor of phosphate groups, which had never been reported before. This approach possessed the benefits of high synthesis efficiency, low cost, and superior reaction system stability, and it provided new insights into the rapid one-pot synthesis of UDP-Gal and high-value glycosidic compounds.

Perfluoroalkyl-Decorated Noble-Metal-Free MOFs for the Highly Efficient One-Pot Four-Component Coupling between Aldehydes, Amines, Alkynes, and Flue Gas CO2.

The non-noble-metal catalysed-multicomponent reactions between flue gas CO2 and cheap industrial raw stocks into high value-added fine chemicals is a promising manner for the ideal CO2 utilization route. To achieve this, the key fundamental challenge is the rational development of highly efficient and facile reaction pathway while establishing compatible catalytic system. Herein, through the stepwise solvent-assisted linker installation, post-synthetic fluorination and metalation, we report the construction of a series of perfluoroalkyl-decorated noble-metal-free metal-organic frameworks (MOFs) PCN-(BPY-CuI)-(TPDC-Fx ) [BPY=2,2'-bipyridine-5,5'-dicarboxylate, TPDC-NH2 =2'-amino-[1,1':4',1''-terphenyl]-4,4''-dicarboxylic acid] that can catalyze the one-pot four-component reaction between alkyne, aldehyde, amine and flue gas CO2 for the preparation of 2-oxazolidinones. Such assembly endows the MOFs with superhydrophobic microenvironment, superior water resistance and highly stable catalytic site, leading to 21 times higher turnover numbers than that of homogeneous counterparts. Mechanism investigation implied that the substrates can be efficiently enriched by the MOF wall and then the adsorbed amine species act as an extrinsic binding site towards dilute CO2 through their strong preferential formation to carbamate acid. Moreover, density functional theory calculations suggest the tetrahedral geometry of Cu in MOF offers special resistance towards amine poisoning, thus maintaining its high efficiency during the catalytic process.

An Efficient One-Pot Synthesis of Pyrido[2,3-c]coumarins via Serial Catalysis and Its Application in Concise Formal Synthesis of Santiagonamine.

Versatile and high-yielding one-pot synthesis of polysubstituted pyrido[2,3-c]coumarins from N-Boc-N-coumarinyl propargylamine derivatives was achieved via serial catalysis using AgSbF6. Using this approach, the concise formal synthesis of santiagonamine was successfully accomplished. This simple and versatile method could be used to increase the potential of the pyrido[2,3-c]coumarin scaffold for diverse synthetic and biological applications.

Highly Efficient One-Pot Synthesis of Hexakis(m-phenyleneimine) Macrocyle Cm6 and the Thermostimulated Self-Healing Property through Dynamic Covalent Chemistry.

Highly efficient one-pot synthesis of hexakis(m-phenyleneimine) macrocycle Cm6 from acetalprotected AB-type monomer, m-aminobenzaldehyde diethylacetal, was successfully achieved based on imine dynamic covalent chemistry and precipitation-driven cyclization. The structure of Cm6 in the solid state was determined using CP/MAS NMR, X-ray single crystallographic analysis, and WAXD. Macrocycle Cm6 is composed of six phenylene and imine bonds facing the same direction, with nitrogen atoms arranged on the outside of the ring, and has a chair conformation, as predicted from DFT calculation. The macrocycle forms π-stacked columnar aggregates and hexagonally closest-packed structure. The cyclization process was investigated using MALDI-TOF MS and NMR. A mechanism of precipitation-driven cyclization based on imine dynamic covalent chemistry and π-stacked columnar aggregation is proposed. Both the nature of imine linkage and the shape anisotropy of the macrocycle played an important role in the single one-pot synthesis. The water-mediated mutual conversion between macrocycle Cm6 and linear oligomers driven by thermal stimulation was analyzed using MALDI-TOF MS and GPC methods. Macrocycle Cm6 with a dynamic covalent imine bond exhibited self-healing properties when stimulated using heat.

An Efficient One-Pot, Three-Component Synthesis of Tetrasubstituted Pyrroles under Catalyst- and Solvent-Free Conditions

AbstractAn environmentally benign, catalyst- and solvent-free, three-component synthesis of tetrasubstituted pyrroles was established. The reaction proceeds via a nucleophilic attack of primary amine on dialkyl acetylenedicarboxylate followed by Michael addition with β-nitrostyrene and successive intramolecular cyclization and aromatization to yield 1,2,3,4-tetrasubstituted pyrroles in good to excellent yields. A wide range of primary amines including aromatic amines and benzylamines were coupled with differently substituted β-nitrostyrenes and dialkyl acetylenedicarboxylate. Furthermore, compared to previous reported methods, the present study is highly atom economical and environmentally benign and can be scaled up.

Design, Synthesis, and Insights into the Redox Mechanism of Highly Efficient One-Pot Cu-ZSM-5 Catalysts for the Reduction of NOx by NH3-SCR at Low Temperatures

Design, Synthesis, and Insights into the Redox Mechanism of Highly Efficient One-Pot Cu-ZSM-5 Catalysts for the Reduction of NO_<i>x</i> by NH₃-SCR at Low Temperatures

A Simple and Efficient One-Pot Solvent-Free Synthesis of Quinazoline Derivatives Catalyzed by Wet Zinc Ferrite in Air Atmosphere

A Simple and Efficient One-Pot Solvent-Free Synthesis of Quinazoline Derivatives Catalyzed by Wet Zinc Ferrite in Air Atmosphere

A convenient synthesis of functionalized trifluoromethylated 2-((isoxazolyl)(aryl)methyl)malononitrile derivatives via one-pot MCRs

An efficient one-pot, three-component reaction for synthesis of trifluoromethylated isoxazolone-tethered trisubstituted methane derivatives was developed by one-pot three-component reaction of 3-(trifluoromethyl)isoxazol-5(4H)-one, malononitrile and aldehydes in the presence of a catalytic amount of triethylamine. Both aliphatic and aromatic aldehydes bearing different functional groups are well tolerated. This work represents the first example of employing 3-(trifluoromethyl)isoxazol-5(4H)-one as one component in MCRs pattern. The structures of new compounds were determined by spectroscopic methods. In addition, a possible mechanism of the reaction was proposed.

Acemannan from Aloe vera Extract: A Catalyst-Free, Approach for the Access of Imidazole-Fused Nitrogen-Bridgehead Heterocycles

Abstract: A series of 2-phenyl substituted imidazo-pyridines, pyrazines and pyrimidines were synthesized through an efficient one-pot, environmentally benign, and regioselective strategy which involves the reaction between 2-bromocarbonyl compounds and 2-aminopyridines, 2-aminopyrazines, 2- aminopyrimidines, respectively using aloe vera/water (3:2) as a green promoting media. To the best of our knowledge, this is the first aloe vera promoted protocol for the synthesis of this important scaffold having potential applications in medicinal and materials chemistry. The use of aloe vera as a biorenewable and biodegradable reaction medium-cum-promoter, operational simplicity, use of readily available substrates, mild reaction conditions, broad substrate scope, short reaction time, easy workup, and high yields, makes the disclosed protocol a superior alternative to existing methods. Substituted imidazo-pyridines, pyrazines and pyrimidines were obtained with 95%, 76% and 84% yields, respectively.

Modular and Selective Access to Functionalized Alkynes and Allenes via the Intermediacy of Propargylic Acetates

We report an efficient one-pot, two-step procedure for the modular synthesis of α-difunctionalized alkynes and trisubstituted allenes by sequential cross-coupling of benzal gem-diacetates with organozinc or -copper reagents in the absence of external transition metals. The intermediacy of propargylic acetates enables the divergent and selective synthesis of these valuable products. This method features its readily accessible substrates, relatively mild conditions, wide scope, and scalability in practical synthesis.

A Simple, Green, and Efficient One-Pot Synthesis of Dihydro­pyrano[3,2-c]chromene Derivatives Using MgMnO3@ZrO2@CoO as a Core–Shell Nanocrystalline Catalyst

A Simple, Green, and Efficient One-Pot Synthesis of Dihydro­pyrano[3,2-c]chromene Derivatives Using MgMnO3@ZrO2@CoO as a Core–Shell Nanocrystalline Catalyst

DBU-Catalyzed Efficient One-Pot Three-Component Synthesis of Aminoquinoline Derivatives via Betti Reaction in Polar Medium and Antidiabetic Activity of the Products

DBU-Catalyzed Efficient One-Pot Three-Component Synthesis of Aminoquinoline Derivatives via Betti Reaction in Polar Medium and Antidiabetic Activity of the Products

Transforming Inert Cycloalkanes into α,ω-Diamines by Designed Enzymatic Cascade Catalysis.

Aliphatic α,ω-diamines (DAs) are important monomer precursors that are industrially produced by energy-intensive, multistage chemical reactions that are harmful to the environment. Therefore, the development of sustainable green DA synthetic routes is highly desired. Herein, we report an efficient one-pot in vivo biocatalytic cascade for the transformation of cycloalkanes into DAs with the aid of advanced techniques, including the RetroBioCat tool for biocatalytic route design, enzyme mining for finding appropriate enzymes and microbial consortia construction for efficient pathway assembly. As a result, DAs were successfully produced by the designed microbial consortia-based biocatalytic system. In particular, the highest biosynthesis productivity record of 1,6-hexanediamine was achieved when using either cyclohexanol or cyclohexane as a substrate. Thus, the developed biocatalytic process provides a promising alternative to the dominant industrial process for manufacturing DAs.

Efficient One-Pot Solvothermal Synthesis and Characterization of Zirconia Nanoparticle-Decorated Reduced Graphene Oxide Nanocomposites: Evaluation of Their Enhanced Anticancer Activity toward Human Cancer Cell Lines.

This study mainly deals with an effective one-pot solvothermal synthetic pathway for the preparation of uniformly dispersed zirconium oxide nanoparticles on the flattened rough surface of reduced graphene oxide (ZrO2/rGO NCs) using the aqueous leaf extract of Andrographis paniculata. After obtaining detailed information on the preparation and characterization, the anticancer activity of the synthesized ZrO2/rGO nanocrystals (NCs) was evaluated on two human cancer cell lines (A549 and HCT116) along with one normal human cell line (hMSC). The 3-[4,5-dimethylthiazole-2-yl]-2,5-diphenyltetrazolium bromide assays revealed that ZrO2/rGO NCs exhibited a dose-dependent cytotoxicity pattern. The cell viability (%) drastically decreases up to 96-98% after exposure to an optimal concentration of 10 ppm nanocomposites. Analysis of both the reactive oxygen species generation and the Annexin V-FTIC staining assays reveal that ZrO2/rGO NCs have the ability to induce apoptosis in A549 and HCT116 cell lines. Thus, the green synthesis of ZrO2/rGO NCs shows potential in developing efficient therapeutic agents for cancer therapy.

A Sc(OTf)3-catalyzed one-pot two-step approach for spiro-oxindole dihydropyridine derivatives initiated by N-olefination of MBH carbonates

An efficient one-pot, two-step, three-component reaction of isatin-derived MBH carbonates, sulfilimines, and epoxides was achieved, thus affording pharmaceutically important spiro-oxindole dihydropyridines.

One-pot, three-component, iron-catalyzed synthesis of benzimidazoles via domino C-N bond formation.

An efficient one-pot, three-component process for the synthesis of benzimidazole derivatives using a catalytic amount of Fe(iii) porphyrin has been developed. The reaction proceeds via domino C-N bond formation and cyclization reactions of benzo-1,2-quinone, aldehydes and ammonium acetate as a nitrogen source to selectively produce benzimidazole. A number of benzimidazole derivatives have been synthesized using this method in high yields under mild reaction conditions.