Propylsulfonic Acid Research Articles

Poly(biphenyl piperidinium) Amphiphilic Membranes Functionalized with Propyl Sulfonic Acid and Octadecyl Side Chains for Vanadium Redox Flow Batteries

Poly(biphenyl piperidinium) Amphiphilic Membranes Functionalized with Propyl Sulfonic Acid and Octadecyl Side Chains for Vanadium Redox Flow Batteries

Ethyl levulinate production from agricultural residue through tin oxide with grafted propylsulfonic Faujasite catalysis

A novel combination of strong Brønsted acidity (B), from propyl sulfonic acid functionalized on H–Y zeolite (HY-PrSO3H); Lewis acidity (L), by dispersion of SnO2; and confinement control showed high reactivity and selectivity in the conversion of cellulose to ethyl levulinate (EL). An optimal catalyst for EL formation was found by combining the Faujasite (FAU) structure, which incorporates strong Brønsted and Lewis acids in a B/L acidity ratio of 3.9. The resulting catalyst showed high yield of EL 63.7, 57.6 and 24.8%, from fructose, glucose, and empty palm fruit bunch (EFB), respectively. By isolating the cellulose from EFB, the yield from cellulose in EFB could be increased to 42.8% with a selectivity of 74.8%. Moreover, the catalyst could be reused up to 3 times with decreased of EL formation; and moreover, 90% of initial activity was regained after regeneration.

Prepared Sulfonic-Acid-Based Ionic Liquid for Catalytic Conversion of Furfuryl Alcohol to Ethyl Levulinate.

Efficient utilization of Brønsted acids has been advanced through the synthesis of a novel pyridinium propyl sulfonic acid ionic liquid catalyst, [PSna][HSO4]. Employing niacin and 1,3-propanesulfonic lactone, the synthesis aimed to achieve a catalyst that combines atom-efficiency with stability. Optimal catalytic activity was demonstrated at a temperature of 110 °C over a 2 h reaction time, resulting in a furfuryl alcohol conversion and ethyl levulinate yield of 97.79% and 96.10%, respectively. Notably, the extraction and recovery of [PSna][HSO4] exhibited commendable repeatability with up to five cycles, maintaining furfuryl alcohol conversion and ethyl levulinate yield at 93.74% and 88.17%, which highlights the catalyst's durability. Density flooding theory (DFT) calculations were employed to determine the most probable reaction pathways and identify all possible transition states and the reaction energy barriers overcome at each step of the reaction.

Magnetic mesoporous zirconium phosphate (MMZP-Pr-SO3H): a highly efficient and reusable catalyst for sustainable preparation of phenyl tetrazole and 2-substituted benzoazoles

Based on the synthesis of mesoporous zirconium phosphate in the presence of magnetic nanoparticles (NPs) and its functionalization with propyl sulfonic acid groups, a new and effective heterogeneous acidic catalyst (MMZP-Pr-SO3H) was prepared.

Silica Functionalized with Propylsulfonic Acid as an Efficient Metal-free Catalyst for Isomerization of Longifolene to Iso-longifolene

Silica Functionalized with Propylsulfonic Acid as an Efficient Metal-free Catalyst for Isomerization of Longifolene to Iso-longifolene

Synthesis and catalytic advantage of a hierarchical ordered macroporous KIT-6 silica

Ordered mesoporous silicas are important technological materials in catalysis, sorption and separation science, however new architectures are desired to improve in-pore accessibility. Here we report the first synthesis of an ordered macroporous KIT-6, obtained by optimizing the ratios of Pluronic P123: sodium dodecyl sulfate cosurfactants, and a 400 nm polystyrene nanosphere macropore template. The macroporous KIT-6 possesses 370 nm macropores in a face-centered cubic arrangement, surrounded by a silica framework comprised of cubic Ia3¯d three-dimensional, intertwined 5 nm mesopore channels. Propylsulfonic acid (PrSO3H) functionalization affords a macroporous KIT-6 solid acid catalyst whose hierarchical pore network permits rapid diffusion and esterification of fatty acids, conferring a five-fold enhancement for palmitic acid esterification compared with a conventional mesoporous PrSO3H/KIT-6, and 33% rate enhancement vs. an ordered macroporous PrSO3H/SBA-15.

Catalytic fructose dehydration to 5-hydroxymethylfurfural on the surface of sulfonic acid modified ordered mesoporous SBA-16

Catalytic application of propylsulfonic acid modified mesoporous SBA-16 for 5-hydroxymethylfurfural (HMF) production was described for the first time. This material (SO3H@SBA-16) was produced by a simple two steps method involving the grafting of mercaptopropyl groups to SBA-16 and oxidation to sulfonic acid groups with H2O2. Using a combination of Fourier transform infrared spectroscopy (FT-IR), energy-dispersive X-ray (EDX) spectroscopy, X-ray photoelectron spectroscopy (XPS), and acid-base titration techniques, the successful immobilization of propylsulfonic acid groups on SBA-16 was assessed. In addition, X-ray diffraction (XRD), N2 adsorption–desorption isotherms, scanning electron microscopy (SEM), and transmission electron microscopy (TEM) analyses confirmed that the mesostructure of SBA-16 was preserved during the grafting of propylsulfonic acid groups. It was found that SO3H@SBA-16 exhibited outstanding catalytic efficiency and recyclability in fructose conversion to HMF. Various reaction conditions were examined and high yield of HMF (91 %) was achieved after 60 min at 110 °C in DMSO/water (2:1, v:v).

Mimicking Enzymatic Non-Covalent Interactions with Functionalized Covalent Organic Frameworks for Improved Adsorption and Hydrolysis of Cellobiose.

Tuning catalytic centers in heterogeneous catalyst, both in a chemical and a spatial manner, is a powerful approach to improve the stability and the efficiency of catalysts. While the chemical aspects are largely understood, the spatial interactions around active sites, comprised of non-covalent interactions, are difficult to maintain and challenging to study. Herein, the unique properties of covalent organic frameworks (COFs) are utilized to establish an ideal reaction environment for the hydrolysis of cellobiose and other common disaccharides in mild, metal-free, and neutral aqueous conditions. The chosen COF, HCl-PSA-IM-COF-OMe ("HCl" for hydrochloric acid, "PSA" for propyl sulfonic acid, "IM" for imidazole, and "OMe" for methoxy), is modified to be ultra-stable in aqueous conditions and possesses sulfonic acid groups for general acid catalysis and for enhanced hydrogen bonding with reactants as well as intraporous chloride anions for oxocarbenium intermediate stabilization. In addition, the system also relies on the differences in adsorptive binding behavior, Kads , of the reactants and the products to the functionalized framework and benefits from a separate physical, kinetic process to boost the catalytic cycle. Due to its stability in aqueous conditions, HCl-PSA-IM-COF-OMe can be recycled and maintains its hydrolytic properties for five cycles before regeneration is needed.

Novel Magnetically-Recoverable Solid Acid Catalysts with a Hydrophobic Layer in Protecting the Active Sites from Water Poisoning

Three novel magnetically-recoverable solid acid catalysts (hydrophobic catalysts Fe3O4@SiO2-Me&PrSO3H, Fe3O4@SiO2-Oc&PrSO3H and hydrophilic catalyst Fe3O4@SiO2-PrSO3H) were synthesized by introducing organic propylsulfonic acid and alkyl groups to Fe3O4@SiO2 nanocomposites. We characterized these catalysts by FT-IR, EDS, XRD, VSM and SEM, and found that they had excellent core-shell structure and magnetic responsiveness. We also explored the impact of surface hydrophobicity on activity and stability of catalysts in ethyl acetate (EAC) synthesis reaction. The results indicated that: for reactivity and reusability, Fe3O4@SiO2-Oc&PrSO3H > Fe3O4@SiO2-Me&PrSO3H > Fe3O4@SiO2-PrSO3H. This was because octyl and methyl groups could build a hydrophobic layer on the surfaces of Fe3O4@SiO2-Oc&PrSO3H and Fe3O4@SiO2-Me&PrSO3H, and this could effectively prevent water molecules from poisoning active sites; the hydrophobicity of octyl was stronger than methyl. Fe3O4@SiO2-Oc&PrSO3H also showed higher catalytic activity in the external aqueous reaction system, which indicated that it had good water toleration. Moreover, we could easily separate Fe3O4@SiO2-Oc&PrSO3H from the reaction mixture with an external magnetic field, in the meanwhile, its reactivity could still remain above 80% after reusing 6 times.

Preparation, characterization and antibacterial activity of new ionized chitosan

In order to improve the solubility and antibacterial activity of chitosan and expand its application range, ionized chitosan (ICS) was successfully synthesized from chitosan through methylation and sulfonation reactions in this study. The chemical structures of the polymers were verified by Fourier transform infrared spectroscopy (FTIR) and 1H NMR, and a series of characterizations of the polymer were carried out by analytical methods such as element analysis (EA), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and X-ray diffraction (XRD). The results showed that the water solubility of the modified ICS was significantly improved. The introduction of propyl sulfonic acid groups with particle size decreasing and potential increasing greatly improved the antibacterial activity of chitosan, indicating that the ICS had the potential as a water-soluble antibacterial agent.

Sulfonic acid functionalized covalent organic frameworks as efficient catalyst for the one-pot tandem reactions

A covalent organic framework containing hydroxyl groups (HO-COF) has been predesigned and synthesized by the cyclotrimerization reaction of acetyls, which was used as a pre-established network to introduce propyl sulfonic acid through post-synthetic modification strategy, for the fabrication of SO3H-COF with graphene-like multilayer structure. SO3H-COF was employed as an effective heterogeneous catalyst for the synthesis of benzimidazoles, the synthesis of benzodiazepines and one-pot reductive amination of carbonyl compounds. The results indicated that the developed protocol has several advantages, such as high activity, broad substrate scope, short reaction time and excellent yields. The distinctive structures of SO3H-COF endowed the fantastic catalytic properties, good stability and circulation performance.

Preparation of Thiazolidin-4-ones Using NiFe2O4@SiO2 Grafted Propylsulfonic Acid as an Efficient Catalyst

Preparation of Thiazolidin-4-ones Using NiFe2O4@SiO2 Grafted Propylsulfonic Acid as an Efficient Catalyst

Catalytic conversion of cellulose to levoglucosenone using propylsulfonic acid functionalized SBA-15 and H2SO4 in tetrahydrofuran

The catalytic conversion of cellulose to levoglucosenone (LGO) was studied using dilute sulfuric acid and propylsulfonic acid functionalized SBA-15 (PS-SBA-15) in tetrahydrofuran (THF). We show that the addition of small amounts of a liquid acid catalyst such as sulfuric acid complements the use of a solid acid catalyst for the conversion of cellulose. Sulfuric acid promotes the depolymerization of cellulose into levoglucosan (LGA). The main role of the solid Brønsted acid catalyst is to dehydrate the LGA into LGO. The addition of low concentrations of H2SO4 to PS-SBA-15 resulted in an increase in LGO yield of up to 37% (from 18% obtained using an equivalent amount of H2SO4 only). Our approach provides a novel alternative for a more environmentally friendly production of LGO.

Phosphotungstic acid and propylsulfonic acid bifunctionalized ordered mesoporous silica: A highly efficient and reusable catalysts for esterification of oleic acid

In phosphotungstic acid aqueous solution, the ordered mesoporous silica molecular sieve (HPW/OMS-SO3H) simultaneously functionalized by phosphotungstic acid (HPW) and propyl sulfonic acid groups (-pr-SO3H) was successfully prepared via a one-pot co-condensation method. The skeleton of the materials was formed based on the simultaneous hydrolysis and co-condensation of 3-mercaptopropyltriethoxysilane (MPTES) and tetraethoxysilane (TEOS) using in situ oxidation of the thiol groups to sulfoacid groups with H2O2. The materials with an ordered 2D hexagonal mesoporous structure and a high specific surface area were confirmed by the results of small-angle XRD, N2 adsorption–desorption, and TEM. The spectroscopy of FT-IR, UV–Vis DRS, XPS, and Raman indicated that the active component of HPW and propylsulfonic acid groups successfully immobilized on the OMS support and a strong interaction existed among silicon hydroxyl and propylsulfonic acid groups with HPW. The esterification reaction of oleic acid with methanol to produce biodiesel over prepared catalyst showed excellent catalytic activity due to the synergistic effect between the HPW and propylsulfonic acid groups. The biodiesel yield of 95.3% was obtained by 0.3HPW/OMS-SO3H-5 catalyst under the optimum reaction conditions. The catalytic performance was not reduced significantly even after five cycles reused, because the strong interaction prevented acid-active component loss from the support. The activation energy of the reaction by the 0.3HPW/OMS-SO3H-5 materials was investigated, which obeyed the first-order kinetics.

Sulfonated β-cyclodextrins: efficient supramolecular organocatalysts for diverse organic transformations

Abstract The present review summarizes various organic transformations carried out by using sulfonated β-cyclodextrins such as β-cyclodextrin sulfonic acid, β-cyclodextrin propyl sulfonic acid, and β-cyclodextrin butyl sulfonic acid as an efficient, supramolecular reusable catalyst under diverse reaction conditions.

Catalytic dehydration of fructose into 5-hydroxymethylfurfural by propyl sulfonic acid functionalized magnetic graphene oxide nanocomposite

Covalent immobilization of propyl sulfonic acid groups on the surface of magnetic graphene oxide is reported as an efficient magnetically recoverable solid acid catalyst for the conversion of fructose into 5-hydroxymethylfurfural (5-HMF). The obtained nanocomposite has advantages of both graphene oxide (high surface area) and magnetic nanoparticles (fast and facile separation by a magnet). The numerous reaction parameters including solvent, reaction time, temperature, and amount of catalyst were optimized to attain maximum yield of 5-HMF. The results revealed that fructose could be effectively transformed into 5-HMF with a yield of 87% under the optimized reaction conditions. The catalyst could be magnetically separated from the reaction mixture. Moreover, the catalyst exhibited high stability and could be reused for at least five times without a discernible loss of catalytic performance.

Efficient catalytic production of levulinic acid over hydrothermally stable propyl sulfonic acid functionalized SBA-15 in γ-valerolactone-water system

To eco-friendly catalyze glucose to levulinic acid, recyclable acid catalyst has been researched. The synthesis process of propyl sulfonic acid functionalized SBA-15 was improved and the hydrophobic treatment was performed. The structure and functional groups of materials were characterized by X-ray diffraction, transmission electron microscopy, N2 adsorption–desorption isotherms, elemental analysis, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy and simultaneous thermal analysis. The catalytic activity, recyclability and hydrothermal stability of CH3-SBA-15-SO3H material were researched. The highest yield of levulinic acid at 61.56% was obtained at 180 ℃ for 2.5 h in γ-GVL-water solvent system, and the yield of levulinic acid was only decreased by 2% after 4 times reuse. The high degree of silicon polycondension and hydrophobic surface of CH3-SBA-15-SO3H were the key to maintain the hydrothermal stability. The CH3-SBA-15-SO3H solid acid had great potential in development and utilization of biomass resources.

High efficiency functionalized hydrophilic cyclofructans as stationary phases in sub/supercritical fluid chromatography

Packed column SFC has become very popular for preparative and analytical separations due to the low cost of CO2, its accessible critical temperature, and pressure, with the additional benefit of a low environmental burden. Currently, there is a shortage of new polar stationary phase chemistries for SFC. In this work, two new functionalized cyclofructan columns are introduced and evaluated for their performance in achiral SFC separations for the first time. Cyclofructan (CF6), a macrocyclic oligosaccharide, was covalently linked with benzoic acid (BCF6) and propyl sulfonic acid (SCF6) groups by ether bonds. Superficially porous particles (2.7 μm) bonded with modified CF6 showed markedly different selectivity than native CF6. In SFC, peak shapes of amines and basic compounds are often compromised. We show that small quantities (~5.7% v/v) of water added to the methanol modifier in CO2 improves peak symmetries of primary, secondary, and tertiary amines. Efficiencies as high as 200,000 plates/m (reduced plate height ~ 1.8) were observed for benzamide and amitriptyline on the BCF6 column. The relative standard deviations (RSDs) of retention times on BCF6 were about 1.4%, and on SCF6 were less than 1%. Amines on the SCF6 column showed plate counts as high as 170,000 plates/m. Tetramethylammonium acetate is examined as an alternative to water in MeOH. A run time of 36 min with methanol, trifluoroacetic acid, triethylamine mobile phase was reduced to <5 min with complete baseline resolution for a set of amines. The new stationary phases allow greener approaches towards solving separation problems.

Catalytic Conversion of Cellulose to Levoglucosenone Using Propylsulfonic Acid Functionalized Sba-15 and H2so4 In Tetrahydrofuran

The catalytic conversion of cellulose to levoglucosenone (LGO) was studied using dilute sulfuric acid and propylsulfonic acid functionalized SBA-15 (PS-SBA-15) in tetrahydrofuran (THF). We show that the addition of small amounts of a liquid acid catalyst such as sulfuric acid complements the use of a solid acid catalyst for the conversion of cellulose. Sulfuric acid promotes the depolymerization of cellulose into levoglucosan (LGA). The main role of the solid Bronsted acid catalyst is to dehydrate the LGA into LGO. The addition of low concentrations of H 2 SO 4 to PS-SBA-15 resulted in an increase in LGO yield of up to 37% (from 18 % obtained using an equivalent amount of H 2 SO 4 only). Our approach provides a novel alternative for a more environmentally friendly production of LGO.

Sulfonate improves water solubility and cell selective toxicity and alters the lysozyme binding activity of half sandwich Rh(iii) complexes.

Introduction of the propyl-sulfonic acid group at N1 of the coordinated 2-(2-pyridyl)benzimidazole ligand (L) in [RhCl(η5-C5Me5)L](CF3SO3) gives rise to a water-soluble complex, which can bind to the model protein lysozyme via non-covalent interactions. The complex shows selective moderate toxicity against Cryptococcus neoformans (MIC = 21.6-43.3 μM) and exhibits no cytotoxicity to healthy HEK293 cells.