Cationic Covalent Organic Framework as an Ion Exchange Material for Efficient Adsorptive Separation of Biomolecules

Although covalent organic frameworks (COFs) have earned significant interest in separation applications, the use of COFs in biomolecule separation remains unexplored. We examined the ionic COF Py-BPy²⁺-COF as an ion exchange material for biomolecule separation. After characterizing the properties of the synthesized COF with a variety of techniques, binding experiments with both large and small biomolecules were performed. High adsorption capacities of amino acids with different hydrophobicity and charge, as well as proteins of different isoelectric points and molecular weights, were determined in batch equilibrium experiments. Desorption experiments with mixtures of model proteins demonstrated an ability to successfully separate one protein from another with the selectivity hypothesized to be a combination of the isoelectric point, hydrophobicity, and ability to penetrate the crystalline material. Overall, the results demonstrated that Py-BPy²⁺-COF can be exploited as a robust crystalline anion exchange biomolecule separation material.

Pt(II)-Decorated Covalent Organic Framework for Photocatalytic Difluoroalkylation and Oxidative Cyclization Reactions

A new covalent organic framework (COF) based on imine bonds was assembled from 2-(4-formylphenyl)-5-formylpyridine and 1,3,6,8-tetrakis(4-aminophenyl)pyrene, which showed an interesting dual-pore structure with high crystallinity. Postmetallation of the COF with Pt occurred selectively at the N donor (imine and pyridyl) in the larger pores. The metallated COF served as an excellent recyclable heterogeneous photocatalyst for decarboxylative difluoroalkylation and oxidative cyclization reactions.

Sulfur-Decorated Hyper-Cross-Linked Coal Tar: A Microporous Organic Polymer for Efficient and Expeditious Mercury Removal

Hyper-cross-linked microporous organic polymers are a class of porous materials that have captured widespread attention owing to their high surface areas and wide range of monomeric sources. Balancing economy with performance is the initial hurdle when designing effective hyper-cross-linked microporous organic polymers. Herein, we demonstrated an inexpensive sulfurated solvent-knitted hyper-cross-linked microporous polymer scaffold, named sulfur-decorated hyper-cross-linked coal tar (CTHP-SES), utilizing coal tar as an aromatic monomer with numerous positions for potential chelation of toxic metals, particularly mercury, from water. The resulting material illustrated selective adsorption of mercury from both water (1037 mg g^-1) and the gas phase (416 mg g^-1) with rapid kinetics (183.67 mg min^-1 g^-1), good recyclability (4 runs), and excellent stability under both strong basic and acidic conditions. CTHP-SES was able to reduce the concentration of the Hg(II) solution from 1 mg L^-1 to 32 μg L^-1 after 10 min due in part to the promising distribution coefficient (K_d = 2.371 × 10⁶ mL g^-1). These results show that CTHP-SES offers a promising and practical platform to cope with a variety of environmental contaminations.

Straightforward and Expeditious One-Pot Tandem Synthesis of 3,5-Diaryl-1,2,4-Selenadiazoles from Aryl Nitriles

A one-pot process for the efficient synthesis of 3,5-diaryl-1,2,4-selenadiazoles from aryl nitriles has been developed. This tandem transformation was performed in excellent yields (91–98%) via in situ selenoamidation and a subsequent oxidative dimerization reaction. This method features relatively mild reaction conditions, operational simplicity, straightforward separation of the products, and the utilization of inexpensive reagents.

Multicomponent Synthesis of Diversified Chromeno[3,2-d]oxazoles

A practical and efficient synthetic procedure to novel chromeno[3,2-d]oxazoles through a one-pot sequential multistep process is presented. This procedure proceeds efficiently in propylene carbonate (PC) as a green solvent and affords a wide range of the chromenooxazole scaffolds.

Micro-flow nanocatalysis: synergic effect of TfOH@SPIONs and micro-flow technology as an efficient and robust catalytic system for the synthesis of plasticizers

The combination of continuous flow technology with immobilizing of only 0.13 mol% of triflic acid (TfOH) on silica-encapsulated superparamagnetic iron oxide nanoparticles (SPIONs) under solvent-free conditions successfully provided a powerful, efficient, and eco-friendly route for the synthesis of plasticizers. The turnover frequency value in micro-flow conditions varied in the range of 948.7 to 7384.6 h^-1 compared to 403.8 to 3099 h^-1 for in-flask. This technique works efficiently, encouraging future applications of micro-flow nano-catalysis in green chemistry.

An innovation for development of Erlenmeyer–Plöchl reaction and synthesis of AT-130 analogous: a new application of continuous-flow method

The first micro-flow Erlenmeyer–Plöchl azlactone reaction and synthesis of N-benzoylglycine carbamide were established.

A Novel pseudo-Four-Component Domino Reaction for the Synthesis of Naphtho[2,1-b]furan-2(1H)-ones Using a Nanocatalyst

In this article, an original one-pot method is utilized to synthesize a variety of derivatives of naphtho[2,1-b]furan-2(1H)-one via a pseudo-four-component domino reaction of aryl aldehydes, acetic anhydride, hippuric acids, and 2-naphthols catalyzed by HSW@SPIONs. This reaction illustrates an array of attractive features including, with particular interest in this report, a convenient and unique process of creating and utilizing a powerful recyclable nanocatalyst.

Synergic effect of nano-catalyst and continuous flow system: Dakin–West reaction catalyzed by Nafion-H@SPIONs in a microreactor

The expansion of practical processes for superferromagnetic nanocatalysts is a very attractive subject.

1-Methyl-3-(propyl-3-sulfonic acid)imidazolium triflate supported on magnetic nanoparticles: an efficient and reusable catalyst for synthesis of mono- and bis-isobenzofuran-1(3H)-ones under solvent-free conditions

An efficient procedure for the synthesis of isobenzofuran-1(3H)-one derivatives in the presence of [HSO₃PMIM]OTf–SiO₂@MNPs as a highly recyclable catalyst under solvent-free thermal conditions and MW irradiation is reported.

Propylphosphonium hydrogen carbonate ionic liquid supported on nano-silica as a reusable catalyst for the efficient multicomponent synthesis of fully substituted pyridines and bis-pyridines

An efficient method for the synthesis of fully substituted pyridines and bis-pyridines in the presence of propylphosphonium hydrogen carbonate supported on nano-silica (PPHC–nSiO₂) as a reusable catalyst under solvent-free conditions is reported.

Chemoselective One-pot Conversion of Primary Alcohols to their Bis(indolyl)methanes Promoted by Bi(NO3)3·5H2O

A new, “green” and efficient one-pot protocol for the synthesis of bis(indoyl)methanes from primary alcohols using Bi(NO3)3 ·5H2O is described. This procedure performs chemoselectively through a solvent-free reaction and the products are obtained in high to excellent yields.

Efficient and Convenient Procedure for Protection of Hydroxyl Groups to the THP, THF and TMS Ethers and Oxidation of these Ethers to their Aldehydes or Ketones in [BPy]FeCl4 as a Low Cost Room Temperature Ionic Liquid

Alcohols were converted to the corresponding THP, THF or TMS ethers in high to excellent yields in 1-n-butylpyridinium chloroferrate media as a stable and low cost room temperature ionic liquid. In addition, oxidation of these ethers to their aldehydes or ketones without any overoxidation reactions in this ionic liquid was also performed.

Ultrasound-promoted greener synthesis of 2,4,5-trisubstituted imidazoles catalyzed by Zr(acac)4 under ambient conditions

A simple, efficient and green procedure has been developed for the synthesis of 2,4,5-trisubstituted imidazoles catalyzed by zirconium (IV) acetylacetonate using ultrasonic irradiation. The present methodology offers several advantages such as excellent yields, simple procedure, short reaction times and milder conditions.

Synthesis of 2,4,5-trisubstituted imidazoles catalyzed by [Hmim]HSO4 as a powerful Brönsted acidic ionic liquid

An efficient and green procedure for the synthesis of 2,4,5-trisubstituted imidazoles with various aldehydes using a catalytic amount of 1-methylimidazolium hydrogenesulfate as an active and low cost Brönsted acidic room temperature ionic liquid has been developed. The ionic liquid was easily separated from the reaction mixture and was recycled five times without any loss in activity.Key words: ionic liquid, 2,4,5-trisubstituted imidazoles, [Hmim]HSO4, aldehyde, benzil.

Efficient, eco-Friendly and Regioselective Method for Thiolysis of 1,2-Epoxides with Diaryl Disulfides in the Presence of Zn/Bi(TFA)3-TBPB or Zn/Bi(OTf)3-TBPB

Diaryl disulfides undergo regioselective ring-opening of 1,2-epoxides in the presence of zinc powder and 3-4 mol-% of bismuth(III) trifluoroacetate or 1 mol-% of bismuth(III) triflate in molten tetrabutylphosphonium bromide (TBPB) to afford the corresponding β -hydroxy thioethers in good to excellent yields.

A novel enamination of β-dicarbonyl compounds catalyzed by Bi(TFA)3 immobilized on molten TBAB

Enamination of a wide variety of primary amines was successfully carried out in the presence of catalytic amounts of bismuth(III) trifluoroacetate immobilized on molten tetrabutylammonium bromide as "green" media under mild conditions. This new system of the catalyst is recyclable and reusable. Generally, the results of the reaction in tetrabutylammonium bromide is better than the previously obtained results in water because of their yields and reaction times.Key words: amine, bismuth compounds, β-dicarbonyl compounds, enamination, ionic liquid.