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As perceived, fiber-reinforced photocuring resins possess various distinctive advantages over traditional reinforced resin systems. This includes a rapid curing rate, energy efficiency, no volatile organic compounds, high strength, good thermal stability, and chemical resistance. Printing 3D composite objects using vat polymerization techniques has been a center of interest where photocuring resins are applied. In our present study, we have synthesized resorcinol-based diglycidyl ether, that is, a resorcinol-based epoxy resin, and further acrylated to the resorcinol epoxy acrylate oligomer. This oligomer was further formulated to photocuring resins using a suitable quantity of reactive diluents and photoinitiators. Now, three types of synthetic fibers, that is, glass fibers, nylon fibers, and polyester fibers, were incorporated in this formulated resin at different loading percentages. The oligomer synthesized was analyzed for structural conformation using Fourier transform infrared spectroscopy and 13C nuclear magnetic resonance. Further, we comparatively examined the rheological behavior of prepared formulations, and compatible formulations were applied to stereolithography 3D printers. Finally, physical, mechanical, thermal, transmittance, and morphological characteristics were comparatively analyzed for prepared UV-cured composites. The outcomes obtained during characterizations of UV-cured composites will be inevitably reflected in 3D-printed objects.

An ecofriendly inorganic–organic hybrid and novel Schiff base complex of copper coated on epoxy-modified Fe3O4@SiO2 MNPs was successfully designed and prepared from readily available chemicals. In this method, a Schiff base complex as a linker is utilized to protect copper nanoparticles to the core–shell Fe3O4 exterior without agglomeration. The resulted Schiff base complex of copper coated on epoxy-modified Fe3O4@SiO2 MNPs was characterized and confirmed via different analyses such as FT-IR, TGA, XRD, VSM, FE-SEM, TEM, ICP, EDX, and BET. The novel catalyst was examined for the synthesis of various chromene-annulated heterocycles through the one-pot three component reaction of aromatic aldehydes, various phenols (2-hydroxynaphthalene-1,4-dione/resorcinol/β-naphthol), and malononitrile in ethanol at reflux conditions. This method includes important aspects like no usage of column chromatography, very short reaction times, simplicity of product isolation using ethanol, excellent yields, simple procedures, and magnetic recoverability of the catalyst. All in all, our method makes a novel and significant advancement in the synthesis of various chromene-annulated heterocycles.

Considering numerous issues due to asphaltene precipitation during production and transportation of crude oil, this work aims to postpone the onset point of asphaltene and improve the stability of its colloids in heavy (S) and light oil (D) samples. For this purpose, water/oil interfacial tension (IFT) is measured to evaluate the effect of surfactants as asphaltene inhibitor on heavy and light oil samples from Iranian south fields. Onset of precipitation from oil samples is revealed by sudden change in IFT between deionized water and oil samples through addition of different fractions of n-heptane as precipitant. Surfactants are used to stabilize the asphaltene colloids and prevent asphaltene precipitation from crude oil. However, crude oils of different properties require investigations for appropriate surfactant at optimum concentration to delay asphaltene precipitation. In this work, three surfactants Linear dodecyl-benzene-sulfonic acid (L–DBSA), dodecyl resorcinol (DR) and nonylphenol (NP) are examined for their retarding capabilities of onset point of asphaltene precipitation in oil samples S and D. Also, the involved mechanisms for addition of surfactant to crude oil are analyzed and interpreted. Enhanced stability of crude oil and degree of postpone in onset point follows the order of L–DBSA > DR > NP for heavy oil S and NP > DR > L–DBSA for light oil D owing to nature and chemical structure of surfactants and also properties of crude oil samples. Furthermore, IFT fluctuations for light and heavy oil are similar but the faster onset point and different values of IFT for light oil arise from unstable nature and density difference.

Organic resorcinol formaldehyde (RF) aerogel was synthesized via the sol–gel process. The synthesized RF aerogel was modified by the incorporation of 1 and 3 wt.% of amine-functionalized graphene oxide (GO) during the synthesis process to prepare RF-GOA. The FTIR results showed that the functionalization of aerogels with amine was successfully conducted. The FESEM images showed that the interconnected 3D porous structure was created in the modified samples GO plates without affecting the porosity of the structure. The UV–Vis results showed that the RF-GOA1 and RF-GOA3 have improved the elimination amounts of antibiotics from 51 to 77% for oxytetracycline and from 65 to 94% for chlortetracycline. The absorption capacity for the neat RF aerogel, RF-GOA1, and RF-GOA3 was determined to be 258, 387, and 278 mg/g for oxytetracycline antibiotics and 326, 472, and 467 mg/g for the chlortetracycline antibiotics, respectively. Optimal pH for RF aerogel, RF-GOA1, and RF-GOA3 was obtained to be 6, 4, and 2 for oxytetracycline and 4, 2, and 6 for chlortetracycline, respectively. In addition, the adsorption data for modified aerogels were suited by the pseudo-second-order model, and the results showed that chemical adsorption was involved in the rapid absorption of antibiotics on modified aerogels.

Catalyst-free and solvent-free three-component tandem approach can synthesize 2-amino-4H-chromene scaffolds by Knoevenagel–Michael cyclocondensation of aryl aldehydes, malononitrile, and resorcinol via visible light irradiation as a green promoter at room temperature. The significant advantages of the present protocol include energy-effectiveness, catalyst-free, excellent yields, solvent-free, operational simplicity, and high atom-economy, commercially accessible inexpensive preliminary substances, so it meets some features of sustainable and green chemistry.

Application of a dynamic covalent chemistry strategy to the reversible reaction system of resorcinol and α, ω-alkanedials [(CH2)m(CHO)2] (m = 2–10) in ethanol in the presence of hydrogen chloride (...

The competitive hydrogenation and hydrodeoxygenation (HDO) of dihydroxybenzene isomers, catechol (1,2-dihydroxybenzene), resorcinol (1,3-dihydroxybenzene) and hydroquinone (1,4-dihydroxybenzene), was studied in the liquid phase over a Rh/silica catalyst at 323 K and 3 barg hydrogen pressure. Under competitive hydrogenation conditions an order of reactivity of ortho > para > meta was observed. Catechol initially inhibited resorcinol and hydroquinone hydrogenation but not HDO suggesting separate sites for hydrogenation and HDO. When resorcinol and hydroquinone were reacted competitively, HDO became the favoured reaction. The data suggested that cyclohexane and cyclohexanone were primary products. At low dihydroxybenzene (DHB) conversion the ratio of HDO products was dependent upon DHB isomer. When all three DHB isomers were reacted together, initially 86% of the HDO yield came from catechol with the rest from hydroquinone. When resorcinol finally reacted, HDO products were produced first. Reaction of DHB isomers in pairs using deuterium instead of hydrogen revealed changes in kinetic isotope effect (KIE). The presence of competing reactants had a dramatic effect on the energetics of hydrogenation and HDO reactions of individual components, reinforcing the view that hydrogenation and HDO are mechanistically separate. This effect on reaction energetics observed when more than one substrate was present, highlights the limitations of studying one single model compound as a route to understanding the processes required for the upgrading of a true bio-oil feed.

A facile two-step method including hydrothermal reaction and activation at high temperature was designed to prepare nitrogen doped copolymer derived carbon materials with melamine(M) as nitrogen source and resorcinol(R)-furfural(F) resin as carbon precursor. The melamine not only introduces nitrogen in the copolymer-based carbon materials but also tunes the pore structure of the obtained samples. The as-prepared nitrogen-rich carbon materials (RMFC-3.6) possess an ultra-high specific surface area of 2572.33 m2 g−1 with ideal channel structure and nitrogen content up to 1.40 wt.%. RMFC-3.6 exhibits excellent adsorption capacity and fast adsorption rate for most dyes. Using Congo red (CR), Rhodamine B (RhB) and Malachite green (MG) as waste water pollutant models, the maximum adsorption capacities of CR, Rh B and MG reached 3207.61, 2947.42 and 5769.23 mg g−1, respectively, much higher than the reported values. Moreover, the adsorption process of RMFC-3.6 has a good correlation with Langmuir isotherms and coincides with pseudo-second-order kinetic models. Significantly, the adsorption capacity retention of RMFC-3.6 for CR after four cycles maintains 93.17%, indicating excellent cycling stability.

A new cocrystal of Vitamin D3 (Cholecalciferol) and resorcinol has been discovered and characterized through experimental cocrystal screening. Its high stability has been studied against light, hea...

A procedure was developed for preparing resorcinolpyromellitein [3,3,7,7-tetrakis(4-hydroxy-2,2ʹ-oxydiphenyl)pyromellitide] by acylation of resorcinol with pyromellitic dianhydride using tin tetrachloride as a catalyst (120–210°С, 30 h, reactant ratio pyromellitic dianhydride : SnCl4 : resorcinol = 1.0 : 2.5 : 5.0). The structure of the target product was proved by elemental analysis, thin-layer chromatography, UV and IR spectroscopy, 1H NMR spectroscopy, differential scanning calorimetry, and high-performance liquid chromatography with mass-spectrometric detection. The synthesized product exhibits increased hydrophilicity and imparts fluorescence properties to aqueous solutions when dissolved in a small amount (5 × 10–4 wt %), which allows it to be recommended as a chemical marker in tracer exploration of oil strata at oil fields.

Sol-gel processing combined with soft templating and gelation-induced phase separation is very sensitive to the precursor sol composition. In this work we present a straightforward synthesis towards hierarchically structured, macroporous carbon/titania monoliths with ordered mesopores derived from resorcinol/formaldehyde monoliths and a glycolated titanium precursor. We demonstrate the influence of various reaction solvents, where diol-based media and the proportion of the catalyst seem to be essential in controlling spinodal decomposition, obtaining similar monolithic structures under different synthesis conditions. Based on these observations, we further homogeneously incorporated TiO2 into the carbon structure by an in situ synthesis approach, obtaining structural features similar to pure carbon materials with surface areas of about 400 m2 g-1 , periodically arranged mesopores with a mean distance of 10-11 nm and cellular macroporosity.

A hybrid material reduced graphene oxide based organic nanocomposite was synthesized from graphite by modified Hummers method, which is further chemically reduced to form reduced graphene oxide (rGO) and with resorcinol through a solvothermal process a reduced graphene oxide-resorcinol (rGO-R) nanocomposite was obtained. The synthesized materials surface morphology and structural compositions were studied through X-ray diffraction (XRD) and scanning electron microscope (SEM) and their optical properties were studied through UV-visible spectroscopy and photoluminescence. The material was further used as a fluorescent chemosensor to detect cerium ion under aqueous conditions. The rGO-R composite's sensing abilities were studied by following parameters viz. pH, reversibility, time and the interference of other probable competing ions. The sensing follows both the photo-induced electron transfer and intramolecular charge transfer processes. © 2021 Chemical Publishing Co.. All rights reserved., Department of Science and Technology, Ministry of Science and Technology, India, डीएसटी: SERB-EMR/2016/005692

An efficient method for the synthesis of benzannelated macrocyclic di- and triperoxides by cyclocondensation of phenol, catechol, resorcinol or hydroquinone with bis-hydroperoxides and formaldehyde in the presence of lanthanide catalysts has been developed. Additionally, by using flow cytometry, it has been shown for the first time in this work that thus-synthesized macrocyclic di- and triperoxides are efficient apoptosis inducers in the tumor cultures Jurkat, K562 and U937 and in fibroblasts.

Sandwich 12·2, macrocyclic 1·3 and box 12·42 supramolecular assemblies were synthesized by the reaction of 1,8-bis(4-pyridylethynyl)anthracene 1 with hydroquinone 2, resorcinol 3 and 1,5-dihydroxynaphthalene 4via hydrogen-bonding interactions, respectively. The formed sandwiches, macrocycles and boxes can further self assemble to form a double-layer supramolecular polymer, nanotubes and a one-dimensional “iron chain type” supramolecular polymer. Investigation of their crystal structures revealed that the distance between two oxygen atoms in a hydrogen bonding donor play an important role in the formation of supramolecular assemblies.

We developed two fast, simple and sensitive spectrophotometric methods for the determination of ceftazidime in drugs by using phenolic reagents resorcinol and 2-methylphenol. The methods are based on a previous antibiotic diazotization in the medium of hydrochloric acid (CHCl=12 M) and its following azo coupling with reagents in an alkaline medium with the formation of effective analytical forms that allow determining ceftazidime and have maximum absorbance at 519 nm and 516 nm for resorcinol and 2- methylphenol, respectively. The azo coupling products of diazotized ceftazidime exhibit effective molar absorptivity in the range of (6.31–6.84)103 M–1 cm–1. Stoichiometric ratios of the azo compounds components were established using continuous variations methods and they were the same in both cases (1:1). The developed methods allow determining from 2.75 to 185.5 g mL–1 of ceftazidime with resorcinol (LOQ=2.54 g mL–1) and 0.32191.3 g mL–1 of ceftazidime with 2-methylphenol (LOQ=0.28 g mL–1). The developed methods have been successfully tested in the analyses of one-component preparations (powders for injection solutions).

To explore the possibility of using a specially functionalized nanoemulsion for the removal of free radical, resveratrol and phenethyl resorcinol were employed to form resveratrol/phenethyl resorcinol mixed active components, and the removal efficiency of free radicals was evaluated. Original nanoemulsion and specially functionalized-nanoemulsion were characterized by DLS and EPR. The free radical scavenging ability of the mixed active components of resveratrol/phenethyl resorcinol was determined as a function of the mass ratio of resveratrol to phenethyl resorcinol, temperature, and ionic strength. In the results, the removal of free radicals by the resveratrol/phenethyl resorcinol nanoemulsion system was found to be more effective than the nanoemulsion alone. At a higher resveratrol ratio, more than 68% of free radicals could be removed. The efficiency was also found to increase with rising temperature. However, efficiency decreased with the increase in ionic strength. In conclusion, compared with conventional nanoemulsion, the combined utilization of nanoemulsion and the mixed active components of resveratrol/phenethyl resorcinol achieved better results for the removal of free radicals because of synergistic effect between nanoemulsion droplets and the mixed active components of resveratrol/phenethyl resorcinol, involving hydrophobic binding, hydrogen binding, and partitioning.

i-Corona[3]arene[3]tetrazines were synthesized from the nucleophilic aromatic substitution reaction of resorcinol and its derivatives with 3,6-dichlorotetrazine in a one-pot fashion under mild conditions. All of the resulting macrocycles adopted 1,3,5-alternate conformation irrespective of the nature of the substituents on both upper- and lower-rims. i-Corona[3]arene[3]tetrazine was found to self-regulate its macrocyclic conformation and cavity to recognize anions with binding constants spanning from 26 M-1 to 2.2×103 M-1 depending on the structure of the anions. The selective binding resulted from a significant interdependent and synergistic effect between multiple tetrazine π/anion and Caryl -H/anion hydrogen bond interactions. Taking advantage of synergistic effect revealed, a cyanobenzene-embedded i-corona[3]arene[3]tetrazine was designedly synthesized and highly selective and very strong affinity toward nitrate with a binding constant of 2.2×105 M-1 was achieved.

The effect of boron nitride (BN) addition in carbon fiber reinforced resorcinol formaldehyde (C-RF) composites was explored in this study. Composites are altered with various weight proportions of ...

A series of binary cocrystals involving the ditopic hydrogen- and halogen-bond (H- and X-bond, respectively) donors resorcinol (res) and hydroquinone (hq), and 1,3- and 1,4-diiodotetrafluorobenzene...

A terpolymer resin derived from Resorcinol, Formaldehyde and Salicylic acid was synthesized through condensation reaction. Transition metal ions namely Mn(II), Co(II), Ni(II), Cu(II), and Zn(II) were incorporated into the resin forming polymer-metal complexes. Both the resin and the complexes were characterized by FTIR, UV–Vis., XRD, 1H NMR, TGA and SEM/EDX. Elemental analysis was carried out to determine the percentage of different elements present in the resin and its complexes. Conductivity measurement data showed higher conductivity of the metal complexes as compared to its precursor resin. The terpolymer resin and its metal complexes were tested against five strains of gram positive bacteria namely; S. aureus, S. mutans, S. pyrogenes, C. xerosis, C. diphtheria, and three strains of gram negative bacteria namely; E. coli, K. pneuomoniae and P. aeruginosa. All the metal complexes exhibited enhanced antibacterial properties as compared to its terpolymer resin. The Mn(II) and Co(II) demonstrated strong antibacterial activity.

We evaluated the performance of a resorcinol–formaldehyde (RF) hydrogel as an adsorbent for removing aqueous cesium ions (Cs+), by synthesizing cylindrical pellets of RF gels under different molar ratios (R/C) between resorcinol (R) and sodium carbonate (C) as the catalyst for the sol–gel polycondensation in the range from 2.5 to 400. The RF gel prepared at R/C = 2.5, containing the greatest amount of sodium ion (Na+), had the greatest Cs+ adsorption amount (0.660 mmol g−1), because Cs+ could be adsorbed on the network structure in the gel through exchange with Na+ at an equal molar ratio, but with the smallest effective diffusion coefficient of Cs+ (1.45 × 10–12 m2 s−1). Kinetic analyses based on the Dryden–Kay and intra-particle diffusion models revealed that the diffusivity of Cs+ in the RF gel depended strongly on the density of the network structure, which can be controlled by varying the R/C ratio.

New calix[4]resorcinols with four anthracene-ended triazolecontaining fragments as rctt- and rccc-diastereoisomers were obtained in two synthetic pathways, namely, by acidcatalyzed condensation of resorcinols with 4-{[1-(anthracen-9-ylmethyl)-1H-[1,2,3]triazol-4-yl]methoxy}benzaldehyde or by the click reaction of 9-(azidomethyl)anthracene with calix[4]resorcinols bearing four terminal acetylene moieties. The compounds obtained demonstrate dual emission in solid state with intensity of low energy band depending on calix[4]resorcinol conformation. The emission in solutions is dominated by anthracene bands, with rccc-isomer showing additional low energy band.

This research investigated chlorinated byproduct formation at Ti4O7 anodes. Resorcinol was used as a model organic compound representative of reactive phenolic groups in natural organic matter and ...

Synthesis of fully eco-friendly thermosets based on renewable resorcinol diglycidyl ether (RE) hardenered with different biobased diamines having aliphatic, cyclic, or aromatic backbones were prepa...

An advanced electroanalytical technique for the simultaneous assessment of environmental contaminant dihydroxybenzene isomers, catechol (CC), hydroquinone (HQ), and resorcinol (RC), has been investigated using palladium nanoparticles (PdNPs) incorporated onto a poly(1,5-diaminonaphthalene) (DAN) matrix over a glassy carbon electrode (GCE). Concurrently, these types of phenols can be assessed by the PdDAN/GCE modified electrode employing square wave voltammetry and cyclic voltammetry (CV) techniques under optimal conditions. This modified electrode has demonstrated linear responses for CC, HQ, and RC from 50.0 to 1000.0 mM; concomitantly, low detection limits of 0.22, 0.22, and 0.47 nM and low quantification limits of 0.740, 0.758, and 1.590 nM, have been, respectively, shown. Successfully, the simultaneous assessment of the three isomers in river stream water, tap water, and underground water has been implemented via the modified electrode under investigation. In comparison to reported studies, the PdDAN catalytic electrode has shown an effective sensitivity, leverage reproducibility, long-term stability, and excellent anti-interference capability for the determination of dihydroxybenzene isomers.

An enantioselective catalytic synthesis of α‐acetoxylated ketones through I(I)/I(III) catalysis using a resorcinol/lactamide‐based chiral iodoarene is reported. Catalyst turnover by in situ generation of the active iodine(III) derivative is achieved by oxidation with mCPBA in the presence of acetic acid. The prior transformation of ketones to easily accessible acetyl enol ethers is beneficial and yields up to 97 % with enantioselectivities up to 88 % ee are obtained using only low catalyst loadings of only 5 mol % under mild reaction conditions., An efficient and easy acetoxylation of ketones via their enolethers is described. With low catalyst loadings of a chiral aryliodine high stereoselectivities can be obtained under mild reaction conditions.

Two liquid-liquid extraction-chromogenic systems for GaIII based on azo dyes (ADs) and xylometazoline hydrochloride (XMH) have been studied. The ADs used were 4-(2-pyridylazo)resorcinol (PAR) and 4-(2-thiazolylazo)resorcinol (TAR). The optimum conditions (pH, AD concentration, XMH concentration, and extraction time) for the formation of ternary complexes of general formula (XMH+)[GaIII(AD2–)2], that are readily extracted into chloroform, have been worked out. The following extraction-spectrophotometric characteristics: absorption maxima (λ), molar absorptivities (eλ), limits of detection (LOD), limits of quantitation (LOQ), constants of extraction (Kex), and fractions extracted (E) have been determined. The system in which AD = PAR has better performance: e512 = 9.9×104 dm3 mol–1 cm–1, LOD = 2.8 ng/cm3, LOQ = 9.4 ng/cm3, log Kex = 4.1, and E = 97%. Extraction equilibrium with this reagent is achieved in a short time (only a few seconds) and the optimum pH interval is broad (5.1–7.8).

H2S can cause multiple diseases and poses a great threat to human health. However, the precise detection of extremely toxic H2S at room temperature is still a great challenge. Here, a facile solvent evaporation induced aggregating assembly (EIAA) method has been applied for the production of ordered mesoporous carbon (OMCs) in an acidic THF/H2O solution with high-molecular-weight poly(ethylene oxide)-b-polystyrene (PEO-b-PS) copolymers as the structure-directing agent, formaldehyde and resorcinol as carbon precursors. Along with the continuous evaporation of THF from the mixed solution, cylindrical micelles are formed in the solution and further assemble into highly ordered mesostructure. The obtained OMCs possesses a two-dimensional (2D) hexagonal mesostructure with uniform and large pore diameter (∼19.2 nm), high surface area (599 m2/g), and large pore volume (0.92 cm3/g). When being used as the resonant cantilever gas sensor for room-temperature H2S detection, the OMCs has delivered not only a superior gas sensing performance with ultrafast response (14 s) and recovery (21 s) even at low concentration (2 ppm) but also an excellent selectivity toward H2S among various common interfering gases. Moreover, the limit of detection is better than 0.2 ppm, indicating its potential application in environmental monitoring and health protection.

Four types of natural oils varied in the viscosity were added to a nitrile butadiene rubber (NBR) loaded with three bonding systems (HRH) consisting of hexamethylenetetramine (HMT), resorcinol and ...

An ion chromatographic method for separation and determination of the sum of the rare earth elements in addition to the individual determination of some heavy metal ions has been developed. The separation has been performed on a mixed bed column, IonPac CS5A containing both anion and cation exchange sites. Selective separation of heavy metals was performed by isocratic elution using pyridine-(2,6)-dicarboxylic acid eluent followed by on-line elution of the total rare earth elements using oxalic acid eluent. Post-column spectrophotometric detection with 4-(2-pyridylazo) resorcinol was then coupled at 530 nm. The separation factors of the different ions were found to be dependent on the eluent concentration, the pH and to a much more extent on the flow rate. The optimized developed method has been validated by its application for the analysis of some heavy metals and the sum of the rare earth elements in a sample from Abu Rusheid mineralization that is considered as a reference material and has then been used for the analysis of two other samples represent two different localities one of which is from Gabal Gattar area while the other is from Abu Tartour phosphate deposits. The optimized method enabled the successful determination of both heavy metals and rare earth elements sum within a total analysis time of about 20 min with high reproducibility.

Here we report the adaptation of formaldehyde crosslinked phenolic resin-based aerogel and xerogel synthesis to ethanol-based solvent systems. Three specific formulations, namely one resorcinol–formaldehyde (RF) and two resorcinol– melamine–formaldehyde (RMF) systems were studied. As-prepared resins were characterized in terms of envelope and skeletal density. Furthermore, resin samples were pyrolyzed and activated in a CO2 gas atmosphere using a single-step protocol. The corresponding carbon materials featured high surface areas, moderate water uptake capacity and thermal conductivities in the 0.1 W.m−1K−1 range, in line with comparable activated carbons. The amount of formaldehyde in the synthesis of the RMF derived carbons proved to be a critical parameter in terms of both structural features and amount of N dopant in the carbonaceous matrix. Furthermore, a high formaldehyde concentration also has a drastic effect on the pore structure of the corresponding RMF carbons, leading primarily to mesopore formation without almost any macropore formation. Perhaps more importantly, the effect of the ammonia curing catalyst concentration on the material microstructure showed the opposite effect as observed in classical, water-based phenolic resin preparations. The ethanol-based synthesis clearly affects the pore structure of the resulting materials but also opens up the possibility to create inorganic/organic hybrid materials by simple combination with classical alkoxide-based silica sol–gel chemistry.

In this contribution, zeolites with different pore sizes and connectivity (MFI 10-10-10R, MTW 12R, Beta 12-12-12R) were prepared in bulk and hierarchical “nanosponge” form and with different composition (aluminosilicate, gallosilicate). Properties of the samples were characterized by X-ray diffraction, argon adsorption, transmission electron microscopy and adsorption of pyridine followed by FTIR spectroscopy. Catalytic performance (conversion of reactants, yields of products and turn-over frequencies) of prepared materials was investigated in the Pechmann condensation of resorcinol with ethyl acetoacetate. The lowest conversion (less than 15%) over the MFI samples suggests that its 10R channels are too narrow for the products to escape from the framework and thus the reaction proceeds mainly on the crystal surface. Conversion of reactants over MTW and Beta zeolites is higher (10%, 35%, 71% and 69% for bulk MTW, nanosponge MTW, bulk Beta and nanosponge Beta, respectively), however, undesired side-products are formed. The hierarchical form of MFI and MTW gives higher conversions and yields of products than their bulk counterparts. Interestingly, the difference between bulk and hierarchical Beta is negligible. The overall performance of aluminosilicates and gallosilicates in the reaction is comparable. Catalytic activity of the samples was determined mainly by their textural properties.

A mild and effective synthesis of resorcinol–furfural (RF) thermosetting resin was proposed with ethanol as a distinctive solvent, which, as a usually neglected factor, was shown to not only help form a homogeneous reaction system but also observably reduce the energy barriers between the early intermediates and transition states in addition reactions by explicit solvent effects, drawn from theoretical calculation conclusions. Besides, the para-additions on aromatic rings were more dominant than ortho-additions with the same reactants, which affected the final link types of monomers verified by Fourier transform infrared spectroscopy and two-dimensional nuclear magnetic resonance tests. The prepared resin can be assigned to a relatively fast gel speed and a high residual mass (65.25%) after pyrolysis in a N2 atmosphere by adjusting the molar ratios of F to R, and the curing of that was a complex reaction, with a curing temperature around 149 °C and an activation energy of about 49.11 kJ mol–1 obtained by the Kissinger method.

The removal of toxic and carcinogenic polycyclic aromatic hydrocarbons (PAHs) from water is one of the most intractable environmental problems nowadays, because of their resistance to remediation. This work introduces a highly efficient, regenerable membrane for the removal of PAHs from water, featuring excellent filter performance and pH-driven release, thanks to the integration of a cavitand receptor in electrospun polyacrylonitrile (PAN) fibers. The role of the cavitand receptor is to act as molecular gripper for the uptake/release of PAHs. To this purpose, the deep cavity cavitand BenzoQxCav is designed and synthetized and its molecular structure is elucidated via X-Ray diffraction. The removal efficiency of the new adsorbent material toward the 16 priority PAHs is demonstrated via GC-MS analyses at ng L-1 concentration. A removal efficiency in the 32%, to 99% range is obtained. The regeneration of the membrane is performed by exploiting the pH-driven conformational switching of the cavitand between the vase form, where the PAHs uptake takes place, to the kite one, where the PAHs release occurs. The absorbance and regeneration capability of the membrane are successfully tested in four uptake/release cycles and the morphological stability.

An amphiphilic tris-urea compound (1) containing hydrophilic resorcinol units was designed and synthesized. Compound 1 formed supramolecular hydrogels in basic buffers, such as glycine-NaOH, phosphate-NaOH, 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES)-NaOH, and borate-NaOH. The optimum pH range of the buffer solution for gelation was 10-11 and insoluble suspensions or solutions were formed when the pH was outside this range. When the borate-NaOH buffer was used, supramolecular hydrogels were formed over a wide pH range (7.5-11.0). The thermal stabilities and viscoelastic properties of the supramolecular hydrogels were determined from the gel-to-sol phase transition temperatures and rheological properties, respectively. The supramolecular hydrogel formed from compound 1 and the borate-NaOH buffer exhibited a pH-responsive reversible gel-to-sol phase transition property. Gel-to-sol phase transition could be achieved by adding NaOH and regelation of the sol was realized by adding an appropriate amount of boric acid. Increasing the amount of the acid resulted in a gel-to-sol phase transition.

A wide-range control over multimodal pore systems in porous monoliths is a key technology for developing functional materials, as the favorable pore structures in different length scales are required to be tailored depending on their application fields. In the alkoxy-derived sol–gel systems of silica and organosilicates, the synthetic methodology of meso- and macroporous monoliths with tunable pore properties has been developed by combining the supramolecular self-assembly of a Pluronic surfactant and polymerization-induced phase-separation techniques. This strategy has been applied to the sol–gel process of phenolic resins, giving rise to the hierarchically porous polymer gels with ordered mesoporosity and the corresponding carbon monoliths after carbonization. However, the controllable size range has been limited so far. This study has explored the relationship between the starting composition and the bimodal pore properties in further detail aiming at a better control of pore properties in phenolic resins. The enlargement of mesopore size has been achieved, yet associated with broadening the mesopore size distribution and coarsening the macropore morphology, resulting in the particle aggregates. The systematical investigation also reveals that the addition of KCl can improve the micelle arrangement in macroframework and provide the narrower mesopore size distribution.

A series of templated solid-state reactions are used to construct the ‘bent’ isomer of the [2.2]cyclophane family of molecules. Small-molecule hydrogen-bond-donor templates based on resorcinol comp...

An efficientconversionof biorenewableferulicacidintobio-catechol hasbeendeveloped.Thetransformationcomprisestwoconsecutivedefunctionalizationsof the sub-strate,that is,C@O(demethylation)andC@C(de-2-carbox-yvinylation)bondcleavage,occurringin one step.The processonlyrequiresheatingof ferulicacidwithHCl(or H2SO4)ascatalystin pressurized hot water(25088C, 50 bar N2). Theversatilityis shownon avarietyof other(biorenewable)substratesyieldingup to 84%di- (catechol, resorcinol,hydro-quinone)andtrihydroxybenzenes(pyrogallol,hydroxyqui-nol),in mostcasesjust requiringsimpleextractionas work-up. ispartof: Angewandte Chemie-International Edition vol:59 issue:8 pages:3063-3068 ispartof: location:Germany status: published

The objective of this study was to develop a reliable visual method for rapid detection of donkey components to protect consumers from commercial adulteration. Six specific loop-mediated isothermal amplification (LAMP) primers targeted at donkey mitochondrial cytochrome b gene were designed, the mitochondrial DNA extraction simplified, the LAMP reaction system optimized, the specificity verified with mitochondrial DNA of horse, pork, cow, sheep, chicken, duck, and rabbit as negative controls, the detection limit determined with gradient dilution of adulterated meat with donkey meat, and the visual LAMP method for detection of donkey-derived ingredient in common meat products established. The results showed that the modified mitochondrial DNA extraction method was simple and repeatable, and the visual LAMP method with 4-(2-pyridylazo)-resorcinol sodium salt as indicator can accurately and specifically detect the donkey meat in common meat products, 1% detection limit. The study provided a promising solution for facilitating the surveillance of the commercial adulteration in processed meat.

A nitrogen doped carbon aerogel was used as a substrate for the atomic layer deposition of TiO2 and ZnO layers in various thicknesses. The bare and composite products were analyzed using Raman spectroscopy, XRD, N2 adsorption, SEM-EDX, TEM, XPS, and ICP-OES and their photocatalytic activity was investigated in decomposing methyl orange dye under UV light irradiation. We investigated the effect of the different metal oxides and their thickness dependence on the photocatalytic activity.

A cloud point extraction-chromogenic system for vanadium determination containing 4-(2-thiazolylazo)resorcinol (TAR), H2O2, H2SO4, and Triton X-100 was investigated. Optimal conditions for the formation and extraction of a 1:2:1 (VV:O22−:TAR) ternary complex with an absorption maximum at 569 nm were found: concentration of TAR (4 × 10−5 mol dm−3), concentration of H2O2 (1.2 × 10−4 mol dm−3), pH (ca 2), mass fraction of the surfactant (3.6%), and incubation time (40 min). The molar absorptivity (e569), Sandell’s sensitivity (SS), limit of detection (LOD) and linear working range (LWR) were 7.4 × 104 dm3 mol−1 cm−1, 0.69 ng cm−2, 1.7 ng cm−3 and 6–510 ng cm−3, respectively. The effect of foreign ions was studied. The developed procedure was applied for the spectrophotometric determination of the total vanadium content in spent silica-supported catalysts and a vanadium-containing dietary supplement.

Heterocyclic and aromatic azo derivatives of pyrocatechol, resorcinol, and salicylic acid have been investigated as collectors for the flotation of sulfide ores. The acid-base properties of the compounds were studied, their solubility in an alkaline solution was determined. It was established that the fixing of reagents on the surface of the ore occurs mainly by the chemical mechanism. Adsorption constants were calculated. It was found that most of the studied reagents exhibit collective properties with respect to sulfide copper—nickel ore. The use of mixtures of azo compounds with potassium butyl xanthogenate leads to an increase in the degree of extraction of nickel and copper, as well as the quality of the concentrates, in comparison with one butyl xanthogenate.

Heterogeneous acid catalysts were prepared by sulfonation of nanoporous carbons (NPCs). The NPCs were produced by pyrolysis of resorcinol-formaldehyde nanoporous resins (NPRs). The NPRs were synthesized as wet gels by condensation of resorcinol and formaldehyde in a sol-gel polycondensation using Na2CO3 as catalyst. A cationic polyelectrolyte (poly(diallyl dimethyl ammonium chloride)) was used as pore stabilizer, allowing to dry the gels in air without any special procedures. Five NPRs with different properties were synthesized by varying the monomer to catalyst ratio (Resorcinol/Na2CO3, R/C). The morphological and textural characterizations of the NPCs were performed by scanning electron microscopy and nitrogen adsorption-desorption isotherms. The results indicate that using a molar ratio of R/C=200, a nanoporous carbon NPC with large surface area (695m2/g) is obtained. This NPC was sulfonated by reaction with three different sulfonating agents: (i) concentrated sulfuric acid; (ii) fuming sulfuric acid and (iii) chlorosulfonic acid in order to obtain a novel Fischer esterification catalyst. The amount of acid groups attached to the NPC surface was determined by titration using a modified Boehm method. The catalytic activity, for Fischer esterification reaction of different sulfonated NPCs, was compared with sulfonated NPRs, sulfonated commercial porous carbons and polymeric acid catalyst (cationic ion exchange resins, sulfonated fluoropolymers). The modification of NPCs with concentrated sulfuric acid seems to render the materials with more catalytic activity. The best sulfonated material NPC (PC200-H2SO4) shows a high catalytic activity for the esterification of acetic acid (90.8%) and oleic acid (60.6%) with ethanol. The conversion and conversion rate values are better than commercial acid catalysts. The results suggest that sulfonated NPC catalysts are promising materials for the synthesis of biodiesel and related reactions. Fil: Tamborini, Luciano Henri. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Química; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Militello, María Paula. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Química; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Balach, Juan Manuel. Leibniz Institute for Solid State and Materials Research; Alemania. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Moyano, J. M.. Universidad Nacional de Rio Cuarto. Facultad de Ingeniería. Departamento de Tecnología Química; Argentina Fil: Barbero, César Alfredo. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Química; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Acevedo, Diego Fernando. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Química; Argentina. Universidad Nacional de Rio Cuarto. Facultad de Ingeniería. Departamento de Tecnología Química; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

In this paper we report the design and synthesis of novel derivatives of the 4H-3,1-benzothiazinone type and heterocyclic analogues, i.e. benzofuro-, azolo- and thieno-1,3-thiazin-4-ones possessing 2,4-dihydroxyphenyl substituent. The compounds were obtained by the one-step reaction of aminobenzamides or heterocyclic aminocarboxamides with aryl-modified sulfinylbis[(2,4-dihydroxyphenyl)methanethione]. Evaluation of their antiproliferative potency against human cancer cell lines showed that the activity of some analogues was similar to that of cisplatin. The highest activity and low toxicity were found for 6-tert-butyl-2-(5-chloro-2,4-dihydroxyphenyl)-4H-thieno[3,2-d][1,3]thiazin-4-one. The structure–activity elucidation reveals that the most active compounds are those with a thienothiazin-4-one and benzofuro[3,2-d][1,3]thiazin-4-one skeleton and the presence of the hydrophobic substituent (Et, Cl) in the benzenediol moiety increases their antiproliferative potency. The ADMET properties of selected compounds including metabolic stability and toxicity profile were estimated in silico. Keywords: 4H-3,1-Benzothiazin-4-ones, Heterocyclic resorcinols, SAR, Antiproliferative activity, ADMET, In silico

The extraction efficiency of the solvent on the polyphenols greatly determines whether the phenol-containing wastewater can be handled well. In this work, liquid–liquid equilibrium (LLE) data for t...

This paper designed and synthesised a series of V-shaped liquid crystal molecules (X-SBAnE) with resorcinol as the core and Schiff base as the mesogenic arms (X-SBAAn). The effects of polar...

BiOBr-based photocatalysts hold great promise in the application of organic wastewater treatment and air purification. However, the catalysis ability of photocatalyst is greatly limited by its poor reduction capacity and intrinsic high recombination rate of photo-generated charge carriers. In this work, a novel direct Z-scheme BiOBr/Bi12O17Br2 photocatalyst is prepared via a facile hydrolysis route at room temperature, which exhibits highly enhanced performance for resorcinol degradation and NO removal than pure Bi12O17Br2 and BiOBr. The formation of the direct Z-scheme heterojunction is substantiated by radical scavenging experiments and the analysis of electronic structure, and it benefits the photocatalytic reaction by accelerating the charge separation and improving the redox ability. Finally, the underlying photocatalytic mechanism is elucidated based on the band structure and radical scavenging experiments. This study provides a facile strategy for bismuth halide Z-scheme heterojunction constructing at room temperature and also sheds light on highly efficient photocatalysts designing.

In this study, the MgFe2O4 nanoparticles were synthesized via a green and simple approach. Then an effective procedure to synthesize 2-amino-7-hydroxy-4H-chromene and tetrahydrobenzo[b]pyran derivatives was established through the chemical reaction between different aldehydes, malononitrile and resorcinol (or dimedone) in the presence of MgFe2O4 nanoparticles as a beneficial catalyst in ethanol as solvent under ultrasound irradiation. Moreover, the synthesized MgFe2O4 nanoparticles were easily recovered by an external magnet and reused for four times without significant loss of their catalytic activity. Simple, fast, effective and eco-friendly as well as quick purification method along with high product yields are some of the advantages of the present chemical reaction.