Convenient One-pot Synthesis Research Articles

Removal of mercury and lead ions from water using bioinspired N3Se3 type small sized moieties.

Mercury and lead toxicity in water has serious repercussions on human health. There is an urgent need to develop effective and efficient small moieties for their removal. The convenient one-pot synthesis of a few N3Se3 type small sized moieties is reported herein. The highest metal ion uptake capacity of Hg(II) and Pb(II) ions was found to be 314.3 mg g-1 and 93.5 mg g-1, respectively, by ICP-MS analysis. These ion uptake values are the highest for small sized moieties known in the literature to date.

One-Pot Syntheses and Enzyme Inhibition Studies of New C-28 Ester Derivatives of Betulinic Acid

Abstract: Betulinic acid and its various synthetic derivatives have been reported to possess diverse biological activities and some of these may serve as useful therapeutic agents for a variety of human disorders. In this perspective, we have now developed convenient one-pot syntheses of new C-28 esters (2-7) of betulinic acid by esterification of the carboxylic moiety of betulinic acid (1) with various alkylating agents. All the target compounds were subjected to enzyme inhibition studies to ascertain their possible therapeutic utility. Compound 5 showed very potent lipoxygenase inhibitory activity with an IC50 value of 13.2 μM, being much lower than the IC50 value of 22.4 μM of baicalein, which was used as the standard. Butulinic acid itself and compound 6 also showed significant inhibitory potential (IC50: 32.4 and 25.1 μM) against the same enzyme. The activities of both compounds 5 and 6 have been justified by intensive docking studies. Compounds 2 and 3 exhibited substantial inhibition (IC50: 18.4 and 21.5 μM) against the enzyme butrylcholinesterase, compared to serine used as the standard (IC50: 7.8 μM).

Preparation and InhA inhibitory properties of novel dehydroacetic acid-derived thiazoles

A series of 4-hydroxy-6-methyl-3-(1-(4-(aryl/methyl)thiazol-2-yl)-1H-pyrazol-3-yl)-2H-pyran-2-ones 3a–h have been synthesized from aryl/methyl halomethylketones and a key pyrazole intermediate 1 using a convenient one-pot synthesis method. All compounds were characterized by NMR and MS, and the structure of three of them (3a, 3b and 3f) was resolved by X-ray diffraction. These heteroatom-rich thiazole compounds were then evaluated as inhibitors of Mycobacterium tuberculosis InhA, a key enzyme involved in the type II fatty acid biosynthesis pathway of the mycobacterium. Although inhibitory activities were found to be rather weak, molecular docking studies were also been carried out to understand a possible mode of interaction with key residues in the enzyme’s active site.

Efficient and Convenient One-pot Synthesis of Quinoxalines Promoted by Schiff base dioxomolybdenum(VI) complex

Schiff base dioxomolybdenum(VI) complex was found to be an effective catalyst for the condensation reaction of benzoins and 1,2-diamines to afford quinoxalines in one-pot reaction. The route provides several advantages such as simple process, mild conditions, low catalyst loadings and environmental friendliness.

Environmental risk mitigation of lambda-cyhalothrin using tryptophan-modified magnetic nanoparticles: A sustainable emergency response strategy

Lambda-cyhalothrin, a synthetic pyrethroid pesticide extensively used in agriculture, poses significant environmental challenges due to its extensive and long-term application. To remediate pollution caused by such organic contaminants, our study introduces a rapid and convenient one-pot synthesis method for creating amino acid-modified magnetic nano-adsorbents (AA-MNPs). Research found that after modification with tryptophan (Trp), the adsorption effectiveness of MNPs on Lambda-cyhalothrin significantly increases. This modification enhances the carbon content of the magnetic nanoparticles, while minimally affecting the magnetic saturation of the MNPs. Trp-MNP exhibited an approximate particle size of 450 nm and a specific surface area of 52.36 m2 g-1. The isotherm and kinetic experiments were well-fitted to the Liu isotherm model and the pseudo-second-order model, respectively. Thermodynamic assessments suggested that the adsorption process is spontaneous and exothermic. Results indicated that the maximum adsorption capacity 144.34 mg g-1 for Trp-MNPs at 298 K, outperforming adsorbents reported in the literature. The half-adsorption time was reduced to 8 min at 298 K with an initial concentration of 60 mg L-1. This enhancement was likely influenced by the aromatic ring modification and hydrophobicity of Trp-MNPs. The study explored potential removal mechanisms from a tri-phase perspective, investigating the interactions between the adsorbent, adsorbate, and solvent.

Manganese(III) Nitrate Complexes as Bench-Stable Powerful Oxidants.

We report herein a convenient one-pot synthesis for the shelf-stable molecular complex [Mn(NO3)3(OPPh3)2] (2) and describe the properties that make it a powerful and selective one-electron oxidation (deelectronation) reagent. 2 has a high reduction potential of 1.02 V versus ferrocene (MeCN) (1.65 vs normal hydrogen electrode), which is one the highest known among readily available redox agents used in chemical synthesis. 2 exhibits stability toward air in the solid state, can be handled with relative ease, and is soluble in most common laboratory solvents such as MeCN, dichloromethane, and fluorobenzene. 2 is substitutionally labile with respect to the coordinated (pseudo)halide ions enabling the synthesis of other new Mn(III) nitrato complexes also with high reduction potentials ranging from 0.6 to 1.0 V versus ferrocene.

A rapid and large volume synthesis of mono-, di-, tri-, and tetra-substituted imidazole derivatives via ultrasonic radiation-driven technique

Sonochemistry under controlled conditions has proven effective in medicinal chemistry and drug development. It can substantially shorten reaction timelines from days or hours to minutes. A convenient one-pot synthesis of 2,4,5-trisubstituted and 1,2,4,5-tetrasubstituted imidazole derivatives catalyzed by PTSA and benzenesulfonic acid in ethanol as solvent, under ultrasonic irradiation and without ultrasound irradiation at 50° C has been achieved successfully. These 2,4,5-trisubstituted and 1,2,4,5-tetrasubstituted imidazole derivatives synthesis were also accomplished using different solvents viz., Methanol, Ethanol, DCM, DMF, Acetonitrile and THF and PTSA as the catalyst. This method yielded the highest % synthesis of 2,4,5-trisubstituted and 1,2,4,5-tetrasubstituted imidazole derivatives with PTSA as the catalyst in solvent ethanol. These reactions were also optimized for % of PTSA catalyst required to obtain the maximum yield of 2,4,5-trisubstituted and 1,2,4,5-tetrasubstituted imidazole derivatives with and without ultrasound irradiation at 50° C. Synthesis of 2,4,5-trisubstituted Imidazole derivatives reaction follows first-order rate kinetics while that of 1,2,4,5-tetrasubstituted Imidazole derivatives reaction follows the second-order rate kinetics. Furthermore, sonochemistry has higher yields, lower cost, easier workups, and higher purity than conventional thermal organic synthesis, which has lower yields, tedious workups, longer reaction periods, lower purity, and numerous byproducts.

A convenient one-pot synthesis of novel heterocyclic systems of 9-chloro-4-methyl-6,11-dihydro-5H-benzo[b]pyrimido[4,5-e][1,4]diazepine and inhibitory evaluation against bromodomain-containing protein 4 (BRD4) enzyme by molecular docking

A convenient one-pot synthesis of novel heterocyclic systems of 9-chloro-4-methyl-6,11-dihydro-5H-benzo[b]pyrimido[4,5-e][1,4]diazepine and inhibitory evaluation against bromodomain-containing protein 4 (BRD4) enzyme by molecular docking

One-Pot Chitin Conversion to High-Activity Antifungal N,N-Dimethyl Chitosan Oligosaccharides.

Chitosan oligosaccharide and its derivatives are known for their diverse biological activities. In this study, we communicate a convenient one-pot synthesis of N,N-dimethyl chitosan oligosaccharide (DMCOS) from chitin via acid-catalyzed tandem depolymerization-deacetylation-N-methylation pathway using formaldehyde as the methylation reagent. The synthesis protocol offers 77 % DMCOS that features a high degree of deacetylation, a high degree of methylation, and a low average molecular weight. Compared to chitosan, DMCOS exhibits superior antifungal activity against Candida species. Mechanism study reveals a previously non-reported hydroxyl group-assisted effect that facilitates the reductive amination reaction under strong acidic conditions. Overall, our findings demonstrate the feasibility of direct synthesis of DMCOS from chitin, highlighting its potential use in anti-fungal applications.

Convenient One-Pot Synthesis of Kynurenic Acid Ethyl Ester and Exploration to Direct Synthesis of Neuroprotective Kynurenic Acid and Amide Derivatives.

Kynurenic acid (KYNA) is an endogenous molecule, which is a non-selective antagonist of ionotropic glutamate receptors and has been found to have neuroprotective activity. A supplement of KYNA may be applicable for the treatment of neurodegenerative disease, but it does not cross the blood-brain barrier due to its polar nature. Therefore, its different esters and amide derivatives were explored as a prodrug, which can cross blood-brain barrier and transform into KYNA in situ. However, many esters and amide derivatives of KYNA are synthesized via coupling reaction or multi-step synthesis using different organic or metallic catalysts. Herein, we developed a novel one-pot, catalyst-free, convenient synthesis of KYNA ethyl esters using aniline and diethyl acetylene dicarboxylate in DMF under heating. We also explored the synthesis of KYNA and KYNA amide derivative in a simple manner with overall good yields via hydrolysis and condensation, respectively.

Convenient One-Pot Synthesis of L2Pd(0) Complexes for Cross-Coupling Catalysis

A convenient one-pot synthesis of (tBu3P)2Pd(0) was successfully carried out by using various air-stable Pd(II) salts, such as Pd(cod)Cl2, Pd(nbd)Cl2, Pd(CH3CN)2Cl2, or Pd(PhCN)2Cl2, without the use of an external reducing agent. Using Pd(cod)Cl2 as the precursor, large-scale synthesis of (tBu3P)2Pd(0) was accomplished in excellent yield and purity. Another protocol was also developed for L2Pd(0) complexes via an atom economical one-pot method by reacting in situ generated LPd(R-allyl)Cl complexes (L = tBu3P, Cy3P, (o-Tol)3P, CataXCium A, AmPhos, QPhos: R = H, Me, Ph) with 1 equivalent of L in the presence of a base with yields ranging from 74% to 92%, although the process can be further optimized. These methods are superior to those reported in the literature.

Expedient synthesis of 1,2,4-triazinyl substituted benzo[c]coumarins via double oxidation strategy

Herein, we report a convenient one-pot synthesis of 1,2,4-triazinyl derivatives of benzocoumarins. The proposed approach consists in the nucleophilic addition of tetrahydrobenzo annulated dimethoxycoumarin to 1,2,4-triazines followed by double oxidation of both dihydrotriazine and tetrahydrobenzo groups with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ). The nucleophilic addition of the dimethoxycoumarin to 1,2,4-triazines was carried out in the presence of three-fold excess of methanesulfonic acid in DCM at room temperature and take place between positions 4 and 5 of coumarin and 1,2,4-triazine, respectively. The double oxidation step was achieved with 3.6 equivalent of DDQ. Selective oxidation of dihydrotriazine moiety, without affecting the tetrahydrobenzo fragment, was achieved using 1.2 equivalent of tetrachlorobenzoquinone (TCQ). The differences in the oxidation with TCQ and DDQ appear to be related to the higher oxidative potential of DDQ in contrast to TCQ. The advantages of the method are the elimination of the use of transition metals, the availability of starting materials, and the simplicity of the procedure. The proposed approach provides a two-step one-pot protocol for the synthesis of triazinyl benzocoumarins, precursors for the preparation of push-pull pyridinyl chromophore.

In situ generation of acyloxyphosphoniums for mild and efficient synthesis of thioesters.

We present a novel approach for in situ generation of acyloxyphosphoniums by premixing iodobenzene dicarboxylates and triphenylphosphine, resulting in efficient thioester synthesis (up to 100% yield). Stable solid iodobenzene dicarboxylates, achieved via carboxylate exchange, serve as hypervalent iodine precursors. The resulting acyloxyphosphoniums allow convenient one-pot thioester synthesis under mild conditions. Our method demonstrates facile acyloxyphosphonium production from iodobenzene dicarboxylates and Ph3P, enabling diverse thioester preparation. ESI-MS analysis confirms acyloxyphosphonium ion formation, pivotal in acylation. This strategy holds potential for combinatorial thioester synthesis and broader nucleophile modification applications.

Boosting zinc storage in potassium-birnessite via organic-inorganic electrolyte strategy with slight N-methyl-2-pyrrolidone additive

The environmental-friendly and inexpensive birnessite is deemed as a potential cathode material for aqueous Zn-ion batteries (AZIBs). However, its electrochemical property is mainly enslaved to the unstable interlayer structure and side reaction aggravated by aqueous solvation. Herein, a potassium-birnessite (K0.14MnO1.96) cathode is prepared with a convenient one-pot hydrothermal synthesis, and a genuine insight into strengthening Zn2+energy storage efficiency via desolvation strategy with a low concentration of N-methyl-2-pyrrolidone (NMP) additive is proposed, which is also supported by the density functional theory (DFT) calculation. According to the result, the N-6 sample with enhanced kinetics and pseudocapacitance characteristics exhibits an optimum performance including terrific coulombic efficiency (CE) of ∼ 99.9%, impressive specific energy of 425.66 Wh kg−1, and long cyclic stability of 95.96% at 1 A g−1 after 2000 charge-discharge cycles, and specifically the cathodic by-product Zn4SO4(OH)6·4H2O as a major factor leading to properties deterioration for AZIBs is barely visible in the N-6 sample. Hence, this work opens up a simple but novel perspective of solvation barrier remission via organic-inorganic electrolyte strategy to promote aqueous zinc storage in birnessite.

A convenient one-pot synthesis, theoretical studies, and NMR-based conformational analysis of nitroarylidene dimalonates

Tandem Knoevenagel-Michael addition of diethyl malonate to nitro-substituted benzaldehydes was found to proceed in a mild and convenient process. The 1H NMR spectra of the products showed significant changes according to the position of the nitro group. Conformational analysis calculations confirmed that in all cases, a structure containing a mirror plane occurred at energies near the ground state. However, for the meta and ortho substituted products, increased steric crowding resulted in decreased rotational freedom of the ethyl substituents. Consistent with the observation of increased steric stress, molecular orbital calculations predicted a higher electrophilic reactivity of the ortho nitro substituted product.

A convenient one-pot synthesis, and characterisation of the ω-bromo-1-(4-cyanobiphenyl-4’-yl) alkanes (CBnBr)

ABSTRACT A convenient synthetic route based on a sodium-mediated aromatic cross-coupling reaction is described for the multi-gram preparation of the ω-bromo-1-(4-cyanobiphenyl-4’−yl) alkanes (CBnBr, n = 2–10). These materials are not only key intermediates in the synthesis of oligomers and polymers but also exhibit fascinating liquid crystal behaviour in their own right. Nematic behaviour is observed for n⩾5, and the nematic-isotropic transition temperature, TNI, increases in essentially a linear manner on n. The properties of the ω-bromo-1-(4-cyanobiphenyl-4’−yloxy) alkanes (CBOnBr, n = 2–9) are also reported, and nematic behaviour is seen for n⩾3. The values of TNI show a weak odd-even effect on n in which the odd members show the higher values. The sense of this alternation is opposite to that seen for the 4-alkyloxy-4’-cyanobiphenyls, and this is attributed to the steric bulk of the bromine atom. The absence of smectic behaviour for both the CBnBr and CBOnBr series is attributed largely to electrostatic interactions that would arise from the concentration of the bromine atoms at the layer interfaces in an interdigitated smectic phase. A comparison of a range of cyanobiphenyl-based materials containing a chain with a terminal polar or polarisable group suggests that their phase behaviour is governed largely by their average molecular shapes.

One-pot synthesis of spiro-3,4-dihydro-2H-pyrroles through tandem nucleophilic cyclisation reaction

A very simple and convenient one-pot synthesis of spiro-3,4-dihydro-2 H -pyrrole has been developed while synthesising the 2,2,5-trisubstituted pyrrolidines. Initially, the Meldrum’s acid has been treated with a,b-unsaturated ketones in presence of anhydrous carbonate base and phase transfer catalyst benzyltriethylammonium chloride in acetonitrile to afford the Michael adduct which is readily converted to the corresponding oxime using standard conditions. The crude oxime is treated directly with p -toluenesulfonyl chloride and in presence of excess organic base results in tandem nucleophilic cyclisation product spirobicyclic as spiro-3,4-dihydro-2 H -pyrrole directly, instead the tosyloxime as product.

Et3NH][HSO4]-Catalyzed One-Pot Solvent Free Syntheses of Functionalized [1,6]-Naphthyridines and Biological Evaluation

We have developed a convenient one-pot multicomponent synthesis of highly functionalized [1,6]-naphthyridines under solvent free condition using [Et3NH][HSO4] in excellent yield. This protocol offers several advantages, including short reaction time, simple experimental workup procedure and no toxic byproducts, avoids the use of toxic organic solvents and anhydrous conditions. Further. we have screened the synthesized naphthyridines for in vitro antibacterial, antifungal and antioxidant activity. Furthermore, a molecular docking study of these compounds was carried out to investigate their binding pattern with the target, β-Ketoacyl-acyl carrier protein synthase III (FabH). Finally, the ADME parameters for these compounds showed good drug like properties and can be developed as oral drug candidates.

Active in Sleep: Iron Guanidine Catalyst Performs ROP on Dormant Side of ATRP.

Copolymers are the answer to property limitations of homopolymers. In order to use the full variety of monomers available, catalysts active in more than one polymerization mechanism are currently investigated. Iron guanidine catalysts have shown to be extraordinarily active in ROP of lactide and herein prove their versatility by also promoting ATRP of styrene. The presented iron complex is the first polymerizing lactide and styrene simultaneously to a defined block copolymer in a convenient one‐pot synthesis. Both mechanisms work hand in hand with ROP using the dominantly present FeII species on the dormant side of the ATRP equilibrium. This orthogonal copolymerization by a benign iron catalyst opens up new pathways to biocompatible polymerization procedures broadening the scope of ATRP applications.

Convenient One-Pot Synthesis of 9H-Carbazoles by Microwave Irradiation Employing a Green Palladium-Based Nanocatalyst

AbstractAn efficient palladium-catalyzed tandem reaction for the one-pot synthesis of 9H-carbazoles under microwave irradiation is developed. This approach involves a sequential Buchwald–Hartwig amination and a direct arylation from affordable and inexpensive anilines and 1,2-dihaloarenes. For the development of this purpose, a novel and magnetically recoverable palladium nanocatalyst supported on a green biochar under ligand-free conditions is used. Compared to other existing palladium-based protocols, the present synthetic methodology shows a drastic reduction in reaction times and excellent compatibility with different functional groups allowing to obtain a small library of 9H-carbazoles in high yields and with good regioselectivity. This procedure represents the first example in the direct synthesis of carbazoles using a heterogeneous palladium nanocatalyst from commercial precursors. To examine the application of this protocol, a direct and scalable synthesis of the bioactive carbazole alkaloid clausenalene from commercially available starting materials is described.